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        ROBERT BRETON v. COMMISSIONER
               OF CORRECTION
                  (SC 19072)
   Rogers, C. J., and Palmer, Eveleigh, McDonald and Robinson, Js.*
      Argued October 21, 2016—officially released May 23, 2017

   Victoria L. Steinberg, pro hac vice, with whom were
Moira L. Buckley and, on the brief, William H. Ket-
tlewell, pro hac vice, and Jason A. Casey, pro hac vice,
for the appellant (petitioner).
   Harry Weller, senior assistant state’s attorney, with
whom were Cynthia S. Serafini, senior assistant state’s
attorney, and, on the brief, Maureen Platt, state’s attor-
ney, and Michael Proto and Marcia Pillsbury, assistant
state’s attorneys, for the appellee (respondent).
                          Opinion

  McDONALD, J. The petitioner, Robert Breton, was
found guilty of two counts of murder and one count of
capital felony for the 1987 stabbing deaths of his former
wife and his son, and was sentenced to death.1 The
petitioner thereafter filed a petition for a writ of habeas
corpus, attacking both his conviction and his death
sentence. This appeal ensued after the habeas court
denied the petition. Subsequent events have rendered
the petitioner’s claims relating to his death sentence
moot; see part II of this opinion; leaving for our consid-
eration those challenging the judgment of conviction.
   The principal issue in those remaining claims con-
cerns defense counsel’s obligation to investigate and
present mitigating evidence that could reduce a defen-
dant’s culpability when the defendant has directed
counsel not to present such evidence and has refused to
aid in the presentation of such evidence. The petitioner
claims, among other things, that his criminal trial coun-
sel provided deficient representation by failing to inves-
tigate evidence that would have revealed that he
suffered from post-traumatic stress disorder (PTSD)
and methamphetamine intoxication at the time of the
offenses, which in turn prejudiced him by depriving
him of a meritorious mitigating defense strategy. Specif-
ically, the petitioner points to counsel’s failure to: (1)
discover transcripts memorializing the petitioner’s
account of fatally stabbing his father in 1966; and (2)
test the petitioner’s blood sample drawn approximately
forty hours after the crimes. The petitioner contends
that, contrary to the habeas court’s conclusions, his
refusal to admit to the 1987 crimes and his instruction
to counsel not to present an extreme emotional distur-
bance defense does not preclude relief because counsel
had not adequately advised him of the evidence that
was available due to their deficient investigation and
they should not have acquiesced to the petitioner’s unin-
formed decision.
  We conclude that counsel must ensure that a defen-
dant has made a knowing and voluntary decision not
to present mitigating evidence. We further conclude
that the habeas court properly denied the petition in
the present case as to the claims related to this issue,
as well as to the petitioner’s other claims challenging
his conviction.
                             I
                   CRIMINAL TRIAL
   The underlying criminal proceedings were the subject
of three previous appeals to this court. See State v.
Breton, 212 Conn. 258, 259, 562 A.2d 1060 (1989) (Breton
I) (reversing trial court’s decision dismissing aggravat-
ing factor of capital felony and remanding case with
direction to proceed with penalty phase); State v.
Breton, 235 Conn. 206, 260, 663 A.2d 1026 (1995) (Breton
II) (affirming judgment of conviction but reversing judg-
ment imposing death sentence—first penalty phase—
and remanding for new penalty phase hearing); State
v. Breton, 264 Conn. 327, 446, 824 A.2d 778 (Breton III)
(affirming judgment imposing death sentence in second
penalty phase), cert. denied, 540 U.S. 1055, 124 S. Ct.
819, 157 L. Ed. 2d 708 (2003). In Breton II, supra, 212–14,
this court set forth the facts that the jury reasonably
could have found at the guilt phase of the proceedings
in support of the conviction. We briefly summarize the
most salient of those facts, and supplement them with
undisputed facts in the record regarding the circum-
stances leading to the present appeal.
   Sometime before 4:30 a.m. on Sunday, December 13,
1987, the petitioner entered the town house apartment
where his former wife, JoAnn Breton, and their fifteen
year old son, Robert Breton, Jr., had resided since the
couple’s divorce in January, 1987. The petitioner was
armed with a knife. He proceeded to JoAnn Breton’s
bedroom, where he viciously beat and stabbed her.
Robert, Jr., came to the bedroom in response to his
mother’s cries, but fled when the petitioner turned the
attack on him. The petitioner pursued Robert, Jr., to
the bottom of the staircase on the first floor, where the
attack resumed. Both Robert, Jr., and JoAnn Breton
sustained multiple knife wounds to the face, chest and
neck. Each bled to death from a knife wound severing
the carotid artery.
  The petitioner left the apartment and, at some point
thereafter, drove to a nearby reservoir. Later Sunday
morning, he called someone to pick him up at the reser-
voir because his truck had gotten stuck. Sunday eve-
ning, he went to work. He made arrangements with
Domenic Aurigemma, a friend and coworker, to retrieve
the truck the next day. When the men met on Monday
morning, December 14, the petitioner asked Aurigemma
to first drive him over to JoAnn Breton’s apartment
because he had repeatedly gotten a busy signal when
he telephoned her over the weekend. Upon their arrival,
the petitioner went to the apartment door but then
returned to alert Aurigemma that he thought that there
was blood on the doorknob. They then called the police.
   After the police arrived, obtained entry to the apart-
ment, and discovered the bodies, they interviewed the
petitioner. They noticed that the petitioner’s hand was
bandaged, with blood around the wound. An investiga-
tion that same day yielded evidence inculpating the
petitioner. One witness reported hearing screams and
then seeing the petitioner leave the apartment at
approximately 4:30 a.m. on December 13. That same
witness also reported having been told by Robert, Jr.,
that the petitioner had threatened to kill JoAnn Breton.
The petitioner was arrested at approximately 8 p.m. on
Monday, December 14, 1987. A search warrant executed
at the petitioner’s apartment yielded a pair of recently
washed sneakers, still wet, that matched bloody foot-
prints in the apartment. At approximately 9 p.m. on
December 14, the police executed a search warrant that
compelled the petitioner to submit to the drawing of a
blood sample. The state never tested that blood sample
to match it to blood at the scene. Instead, a second
sample was drawn and tested by the state in March,
1989, by agreement of the parties, after defense counsel
moved to suppress the first sample on the ground that
the warrant affidavit contained false statements attrib-
uted to the petitioner.
  Approximately one month before jury selection was
to commence, defense counsel requested that the court
order a competency evaluation of the petitioner due to
concerns arising from their conversations with him.
The trial court, Heiman, J., ordered an independent
evaluation by a team of clinicians, who later reported to
the court that the petitioner understood the proceedings
against him and was able to assist in his defense.
   While jury selection was in progress, defense counsel
raised further concerns to the court when responding
to the deadline for giving notice as to whether they
would be presenting any expert testimony during the
guilt phase in support of defenses relating to the peti-
tioner’s mental state. See Practice Book § 40-18. Coun-
sel informed the court that they believed that there was
important evidence related to the petitioner’s mental
state that could provide the jury with a basis to convict
the petitioner of the lesser offense of manslaughter.
Nevertheless, the petitioner had told counsel that he
did not want them to present a defense of extreme
emotional disturbance.2 Counsel explained that they
believed that they must acquiesce to the petitioner’s
wishes but asked the court to confirm the petitioner’s
position. The trial court then engaged in a colloquy
with the petitioner to confirm that he understood that
evidence of extreme emotional disturbance could
reduce his culpability from murder to manslaughter,
but that he had nonetheless instructed his counsel not
to file ‘‘any notices of claims of extreme emotional
disturbance’’ and, additionally, that he had instructed
them not to produce ‘‘any psychiatric evidence’’ at the
guilt phase of trial. After receiving that confirmation,
the court found the petitioner competent to make this
decision. The court informed the petitioner that such
a defense still might be presented if he later changed
his mind. The court also informed the petitioner that
his wishes did not foreclose the possibility that the
court could charge the jury on extreme emotional dis-
turbance if the evidence warranted such an instruction.
The state’s attorney confirmed on the record his under-
standing that defense counsel had not precluded the
presentation of expert testimony relating to the petition-
er’s mental condition at the penalty phase.
  During the guilt phase of trial, the defense solely
advanced a theory of reasonable doubt. Counsel cross-
examined the state’s witnesses in an effort to call into
question the credibility of the eyewitness identification
and the physical evidence linking the petitioner to the
crime scene. In their case, defense counsel presented
only three witnesses. The testimony of those witnesses
was intended to establish that the petitioner had cut
his hand at work, many hours after the crimes.
   Before the defense rested, counsel asked, outside the
presence of the jury, for certain matters to be placed
on the record. First, defense counsel notified the court
that the petitioner had elected not to testify. The court
confirmed with the petitioner that he understood that
he had the right to testify, but did not want to do so.
Second, defense counsel expressed their concern that,
despite repeated discussions with the petitioner, most
recently that same day, he had refused to accept their
advice to allow them to present an affirmative defense
in mitigation. They asked the court to confirm the peti-
tioner’s decision. Before eliciting any statements from
the petitioner, the court explained that it had no knowl-
edge of the substance of the petitioner’s discussions
with counsel and was not seeking such information, as
the court should not be privy to such matters. The court
then explained to the petitioner that the presentation
of certain evidence could result in a conviction of a
lesser degree of homicide and urged him to give serious
consideration to counsel’s advice, pointing out that the
court’s previous denial of defense counsel’s motion for
a judgment of acquittal meant that there was sufficient
evidence to present the capital felony and murder
counts to the jury. The court took a short recess to
afford the petitioner an opportunity to consult with
counsel. When court reconvened, the petitioner con-
firmed that he had had a chance to discuss all aspects
of the case with counsel, and counsel confirmed that
the defense had no further evidence to present. After
the state rested, the court gave a charge to the jury
that included an instruction that, if it found that the
petitioner had acted under the influence of an extreme
emotional disturbance for which there was a reasonable
explanation or excuse, it could find the petitioner guilty
of manslaughter in the first degree instead of murder.
The jury returned a verdict of guilty of murder and
capital felony.
   The first penalty phase proceeded before the same
jury approximately five months later, at which time
defense counsel presented evidence of mitigating fac-
tors. Mitigating factors also were presented at the sec-
ond penalty phase hearings heard by a three judge panel
eight years later, following this court’s reversal of the
judgment imposing the death sentence in the first pen-
alty phase. The primary evidence came from two expert
witnesses, Walter Borden, a psychiatrist who had con-
ducted a forensic psychiatric evaluation of the peti-
tioner, and Anne Phillips, a clinical psychologist who
had administered a battery of psychological tests to
the petitioner. Borden and Phillips both diagnosed the
petitioner as suffering from a severe mixed personality
disorder with borderline schizoid, paranoid, and
depressive features. Both experts opined that, at the
time of the offenses, the petitioner suffered from
extreme emotional disturbance and his mental capacity
was significantly impaired.
   Borden’s testimony was of particular significance.
He had interviewed the petitioner on four occasions,
beginning just two months after his arrest, in February,
1988, and ending in December, 1988. Borden also elic-
ited background information from certain members of
the petitioner’s family, and reviewed psychological
reports and certain public records pertaining to the
petitioner. Those records included a presentence inves-
tigation report relating to the petitioner’s conviction of
manslaughter for killing his father twenty-one years
before the petitioner killed his former wife and his son.
   Borden testified that the petitioner’s early childhood
and adolescence were replete with horrific neglect,
abuse and abandonment—some of the worst Borden
had ever encountered—that had significantly affected
the petitioner psychologically. Borden described those
circumstances at length, which this court recounted in
Breton III, supra, 264 Conn. 340–42, 371–72. He
described the petitioner’s father as a heavy drinker who
was abusive and threatening toward the petitioner and
others, and who routinely carried a knife. Id., 342.
   Borden recounted the following information that he
had elicited regarding the two events that are relevant
to the petition presently before us, which we memorial-
ized in Breton III: ‘‘On December 3, 1966, the [petition-
er’s] father left the house to go drinking. It was later
reported that, while out drinking, the [petitioner’s]
father stated that the time had come to kill the [peti-
tioner, who was then nineteen years old]. The [peti-
tioner] was at home with his grandmother, who had just
prepared a meal for them to eat, when the [petitioner’s]
father came in, threatened the [petitioner], pushed the
kitchen table against him and threw him up against the
wall. The [petitioner] retreated into the bathroom to
escape from his father and told his grandmother to
call the police. The [petitioner’s] father then attacked
[the] grandmother.
   ‘‘The [petitioner’s] memory about what happened
next was not clear. Borden testified that the [petitioner]
told him that he remembered picking up a knife and
seeing his father fall, apparently hurt. The [petitioner]
did not remember stabbing him, however. The [peti-
tioner] then ran out of the house, found a police officer
to whom he indicated that his father had been hurt and
brought the officer back to the house. The [petitioner’s]
father died of multiple stab wounds to the chest and
face. Ultimately, the [petitioner] confessed to the kill-
ing. He pleaded guilty to manslaughter and received a
suspended sentence. Borden testified that the [peti-
tioner] told him that he did not clearly recall stabbing
his father, but admitted that he must have done so.
   ‘‘Shortly after the [petitioner] killed his father, he met
his wife, JoAnn Breton. He married her in December,
1967, within a few days of the first anniversary of his
father’s death. The [petitioner] was very dependent on
his wife for stability and psychological support, but
their marriage was stormy. Borden testified that the
[petitioner] was pathologically jealous of other men,
paranoid and delusional, and that these conditions
derived from a belief that he could not be loved and
from a profound distrust of other people.’’ (Footnotes
omitted.) Id., 342–43.
   ‘‘When the [petitioner] was laid off [from his job in
1985], he became depressed and started drinking heav-
ily and taking pills. The relationship between him and
his wife worsened. . . . Divorce proceedings were ini-
tiated in July, 1986, and were finalized in January, 1987.
   ‘‘During this period the [petitioner] continued to
become more depressed and to drink heavily. He also
took the prescription drugs Desoxyn and Fiorinal.
Desoxyn is an amphetamine with a potent stimulant
effect. Borden testified that it was the worst medication
that could have been prescribed for the [petitioner]
because it would have exacerbated his depression and
paranoia and could trigger violent behavior. He also
testified that using the drug in combination with alcohol
would be ‘like throwing gasoline’ on a simmering fire.
   ‘‘Borden testified that the [petitioner] reported to him
that he was extremely depressed during the month of
December, 1987. His birthday, the anniversary of his
father’s death and his wedding anniversary all occurred
in that month. It would have been his twentieth wedding
anniversary that year. [He felt abandoned by the fact
that his former wife and his son were planning to leave
for Florida on December 17, and would be away for
Christmas.] . . .
   ‘‘On December 12, 1987, the [petitioner] went to his
former wife’s house in connection with one of [the
various] tasks [that he had recently undertaken in the
hopes of reconciling with her]. While there, he took her
keys. That evening, the [petitioner] went to a bar. He
met a woman there . . . and took her back to his
house, where he attempted unsuccessfully to have sex-
ual intercourse with her. At some point, he took the
woman home and then returned to his own house. He
then noticed the keys that he had taken from his former
wife’s house and decided to return them to her and to
try to talk to her. By then, it was very early in the
morning of December 13.
  ‘‘Borden testified that his understanding of the events
that happened next was based on [his first] interview
with the [petitioner] on February 20, 1988.3 The [peti-
tioner] told him that, as he parked the car in the parking
lot [at] his former wife’s house, he thought that he saw
someone walking around [outside].4 He then ‘strapped
on’ a knife, went to the door and let himself in with
the keys. [The petitioner was wearing gloves.] The [peti-
tioner] reported to Borden that, at that time, he felt
nervous, scared and unsure of himself. He laid the keys
on an ironing board and then returned to the door,
intending to leave. Instead, he went down into the base-
ment. He did not know why. At some point, he went
back up to the first floor and stood for a while. He then
decided to go upstairs to his former wife’s bedroom.
The [petitioner] reported to Borden that he still did not
understand what he was doing. The [petitioner] entered
his former wife’s bedroom, knelt on the bed and
grabbed her. She screamed. The [petitioner] reported
to Borden that he just wanted to talk to her at that
point, but was unable to speak. His former wife then
yelled, ‘Bobby, call the cops, somebody is hurting me.’
   ‘‘Borden testified that, at this point in the narrative
. . . the [petitioner’s] demeanor changed dramatically.
He began crying, sweating and trembling. In this agi-
tated state, the [petitioner] reported to Borden that he
had been trying to keep his former wife from yelling,
not trying to hurt her. He recalled pushing her face
down, wrestling on the bed with her and falling onto
the floor. He found himself sitting on top of her and
hitting her to keep her from yelling. She continued to
scream to ‘Bobby’ that someone was trying to rape her.
   ‘‘At some point a light went on in the hall next to
the bedroom. When the [petitioner] looked up he saw
someone standing in the doorway. The [petitioner] did
not know who it was. At that point, the [petitioner]
took the knife in his hand. Borden testified that the
[petitioner’s] description of his feelings at that time
were ‘very similar [to those that he had described having
at the time of] the death of his father where he described
himself recalling, seeing the hand, his hand and the
knife, not knowing what happened. . . . [I]t’s like he
didn’t feel like he took the knife, he felt like his hand
did it. It was a dissociative, it was not part of him.’
   ‘‘The [petitioner] reported to Borden that he did not
recognize the person in the doorway. He said to his
former wife that it was not ‘Bobby,’ but she said that
it was. The person in the doorway then said something
to the [petitioner]. The [petitioner] reported to Borden
that he believed that the words were, ‘Dad, I love you.’
At that point, the [petitioner] saw his own arm go out
and hit the person in the doorway. He could not clearly
see the person he was striking because the light was
behind that person.
   ‘‘Borden testified that, during this part of the [peti-
tioner’s] narrative to him, the [petitioner] was extremely
emotional, trembling and crying and appeared to be
racked and tormented by his recollection. Borden testi-
fied that it was his impression that the [petitioner] was
‘back in that room’ as he reported the events. The [peti-
tioner] reported that he hit the person in the doorway
and saw something gushing out of his neck or head and
heard something gasping and gurgling. At that point,
the [petitioner] recognized his son.
  ‘‘The [petitioner] then heard his former wife calling
him and he returned to the bedroom. She asked the
[petitioner], ‘[W]hy, Bob?’ The [petitioner] then grabbed
her hair and felt his hand hit her. He heard gurgling
and then a crash. He left the bedroom and, as he started
down the stairs, saw his son lying at the bottom of the
stairs on the floor, shaking. At that point, he went back
into the bedroom and knelt next to his former wife,
who was lying on the floor and asked, ‘[W]hy, why.’ He
told her that he just wanted to talk, but then he hit her
with his hand again.
  ‘‘Borden testified that, at this point in the interview,
the [petitioner] said, in reference to what happened
next, ‘God, no, no, no, I didn’t do that.’ The [petitioner]
reported that he left the bedroom and went back down-
stairs. His son was lying dead at the bottom of the stairs
with his eyes open and looking at the [petitioner]. The
[petitioner] said to his son, ‘[T]hank you for the birthday
card,’ and then stabbed him in the neck.5
   ‘‘Borden testified that, while the [petitioner] was
reporting this portion of the narrative, he was saying,
‘[W]hy do I remember so much? Why do I have to
remember?’ and ‘[W]hy, why, why.’ He also continued
to cry and to be in an extreme emotional state. After
describing his last act, however, his demeanor changed
instantaneously, as if he had awoken from a nightmare.
Borden testified that he could never persuade the [peti-
tioner] to talk about the events surrounding the murders
again. . . .
   ‘‘Borden testified that the [petitioner’s] experience
of his hand as not being a part of himself was an example
of the depersonalization that borderline personalities
are prone to experience. Borden also testified that
depersonalization is a defense mechanism developed
by children who have been subjected to chronic severe
abuse. As adults, such persons are prone to go into a
dissociative state under severe stress.
   ‘‘Borden testified that, in his opinion, at the time
of the offense, the [petitioner’s] ability to conform his
conduct to the requirements of the law was significantly
impaired; his mental functioning was significantly
impaired; he suffered from a mental disease or defect,
namely borderline personality disorder; and he was
severely mentally ill. He also testified that the [peti-
tioner] suffered from an extreme emotional disturbance
at the time of the offense.’’ (Footnotes added.) Id.,
344–49.
   The three judge panel before which the second pen-
alty phrase was heard made findings consistent with
those found by the jury in the first penalty phase. The
panel found that the state had proved beyond a reason-
able doubt that the murders had been committed in an
especially cruel manner. Id., 335–36. The panel found
that the petitioner had not proved that he suffered from
an extreme emotional disturbance, but had proved
other mitigating facts, including that he was neglected,
abandoned and the product of an abusive family unit
during his childhood. Id., 336 and n.8. The panel con-
cluded that none of the proven mitigating facts alone
or in combination constituted mitigation. Id., 336. In
accordance with its findings, the panel imposed a sen-
tence of death. Id. The petitioner directly appealed from
the judgment imposing this sentence to this court. Id.
   While the appeal in Breton III was pending, the peti-
tioner filed a petition for a new trial, claiming that two
transcripts of the petitioner’s account of the 1966 killing
of his father, which came to light for the first time
during the state’s cross-examination of Borden at the
second penalty phase hearing, constituted newly dis-
covered evidence. One transcript was from a police
interview conducted hours after the crime; the other
was from the coroner’s inquest. The petition alleged that
the transcripts would have led to a different outcome
because the petitioner’s dissociated mental state
reflected in the 1966 transcripts would have led Borden
to diagnose the petitioner as having a significant dissoci-
ated mental state at the time of the 1987 homicides
that could have rendered him legally insane. This court
continued the appeal in Breton III to allow that petition
to proceed, after the petitioner argued that a hearing
on the petition would provide a crucial factual underpin-
ning for a related claim in the appeal. Id., 354. New trial
counsel ultimately withdrew that petition with preju-
dice, following Borden’s clarification that further test-
ing would be necessary to determine whether the
petitioner was legally insane at the time of the offense.6
Id. The appeal in Breton III proceeded, and this court
affirmed the judgment imposing a sentence of death on
the petitioner. Id., 446.
                            II
                    HABEAS TRIAL
   Some prefatory comments are necessary to explain
the scope of our review of the habeas proceedings.
After his judgment of conviction and sentence became
final, the petitioner filed an amended petition for a writ
of habeas corpus, claiming that constitutional errors
had infected every stage of the criminal proceedings—
guilt phase, second penalty phase, petition for a new
trial, and appeal. The habeas court, Schuman, J., denied
the petition. The petitioner appealed from that judg-
ment to the Appellate Court, and then moved to transfer
the appeal to this court.
   Following our grant of the motion to transfer, we
issued our decision in State v. Santiago, 318 Conn. 1,
122 A.3d 1 (2015), which effectively narrowed the issues
that we must consider in the petitioner’s present habeas
appeal. In Santiago, this court held that, in light of
the 2012 public act prospectively repealing the death
penalty; Public Acts 2012, No. 12-5; the execution of
offenders who committed capital felonies prior to the
act’s effective date would violate the state constitution’s
prohibition against cruel and unusual punishment. State
v. Santiago, supra, 8–9. The parties in the present case
agreed at oral argument before this court that Santiago
rendered all of the petitioner’s claims challenging his
sentence of death moot, as the petitioner is now entitled
to seek to have his sentence corrected to life imprison-
ment without the possibility of release. Therefore, the
discussion of the habeas proceedings that follows is
limited to the petitioner’s claims that relate to the judg-
ment of conviction.
   In the operative petition, the petitioner asserted the
following claims that are relevant to the present appeal.
First, he alleged guilt phase counsel rendered ineffec-
tive assistance by: (a) failing to discover the two 1966
transcripts, which could have ultimately established
that the petitioner suffered from PTSD with dissociative
features during the 1987 crimes; (b) failing to test the
blood sample taken from the petitioner approximately
forty hours after the 1987 crimes (first blood sample),
which had remained in the state’s file until discovered
by habeas counsel, and which could have established
that he suffered from methamphetamine (Desoxyn)
intoxication during the commission of the offenses; and
(c) presenting a marginal reasonable doubt defense to
the exclusion of a meritorious extreme emotional dis-
turbance defense. Second, he alleged that he had
received ineffective assistance of counsel in his petition
for a new trial because counsel had withdrawn the
meritorious petition with prejudice. Third, the peti-
tioner alleged that the cumulative effect of counsel’s
deficient performance regarding the aforementioned
matters constituted the prejudice necessary to establish
ineffective assistance of counsel, as well as a violation
of his right to due process. Fourth, the petitioner alleged
that the state’s failure to disclose the 1966 transcripts
constituted the suppression of material, exculpatory
evidence in violation of Brady v. Maryland, 373 U.S.
83, 87, 83 S. Ct. 1194, 10 L. Ed. 2d 215 (1963).
  Hearings on the habeas petition took place in 2011—
twenty-four years after criminal trial counsel was
appointed, and twenty-two years after the guilt phase
of the criminal trial concluded.7 Although we explore
the details of this evidence in part III of this opinion
in our analysis of the petitioner’s specific claims, we
briefly summarize that evidence to provide context for
the habeas court’s decision.
   The petitioner proffered testimony from Alan
McWhirter and Richard F. Kelly, who represented the
petitioner at the guilt phase and the first penalty phase,
as well as from the other attorneys whose performance
at other stages of the criminal proceedings was alleged
to be deficient. McWhirter and Kelly had little recall of
the details of their communications with the petitioner
and their investigatory strategies due to the exception-
ally long time that had lapsed since they represented
the petitioner. Defense counsel clearly recalled, how-
ever, that the petitioner had consistently taken the posi-
tion that he did not commit the crimes and had
consistently refused to allow them to present any
defense that would be tantamount to an admission that
he had done so. They acknowledged that they had
believed all along that a reasonable doubt defense had
little chance of success. Nonetheless they pursued that
strategy because (1) they believed that the petitioner
had the right to decide whether to effectively admit
that he had committed manslaughter, and (2) the peti-
tioner had suggested that he would take the stand to
deny having committed the crimes if counsel put on
evidence suggesting that he had done so. Defense coun-
sel did not believe that they had specifically discussed
PTSD with the petitioner, but they recalled discussing
the petitioner’s drug and alcohol abuse. McWhirter testi-
fied that defense counsel had recognized that intoxica-
tion ‘‘would possibly be a defense we could raise
depending on whether it was intention[al], uninten-
tional, or whatever. Obviously it never got raised
because [the petitioner] would not let us go in that
direction.’’
   The petitioner also proffered documentary evidence
and expert witnesses. The petitioner presented expert
opinion that the 1966 transcripts would have provided
significant evidence that the petitioner was in a dissoci-
ative state when he killed his father, which was reflec-
tive of PTSD resulting from prior childhood trauma.
The experts further opined that this evidence, in combi-
nation with the petitioner’s account of the 1987 crimes
to Borden and subsequent interviews or testing, demon-
strated that he suffered from PTSD with dissociative
features during the commission of the 1987 crimes.
  The petitioner also presented expert testimony
extrapolating, on the basis of the level of methamphet-
amine detected when habeas counsel tested the first
blood sample in 2005: (a) a range of the level of the
drug in the petitioner’s system when the blood was
drawn in 1987; and (b) from that range, a range of the
level of the drug in his system forty hours earlier when
he committed the crimes. The petitioner presented
expert opinion that levels in this range would have
caused the petitioner to suffer methamphetamine intox-
ication.8 One of the petitioner’s experts, Neil Blumberg,
a psychiatrist, opined that the petitioner had six mental
disorders at the time of the crimes—chronic PTSD,
depressive disorder not otherwise specified, amphet-
amine intoxication, amphetamine abuse, alcohol depen-
dence, and personality disorder not otherwise specified
with borderline features—that collectively had caused
an extreme emotional disturbance. Another expert,
Pablo Stewart, a psychiatrist, opined that the exacerbat-
ing effect of methamphetamine intoxication on preex-
isting PTSD or the methamphetamine intoxication
alone had caused an extreme emotional disturbance at
the time of the crimes.
  Finally, the petitioner presented testimony from an
experienced capital defense attorney that competent
counsel defending such cases would have investigated
these matters. This expert opined that counsel should
not acquiesce to a defendant’s wishes whether to pre-
sent such evidence, and should make continuous efforts
to persuade a defendant to present such evidence.
  The respondent, the Commissioner of Correction,
proffered numerous exhibits relating to defense coun-
sel’s investigation and presented his own toxicology
experts on methamphetamine intoxication. Those
experts opined that, because of various factors, a single,
eighteen year old blood sample could not yield evidence
to reliably establish a level of methamphetamine in a
person’s system forty hours before it had been drawn.
The respondent did not offer any experts on PTSD, but
he cross-examined the petitioner’s experts as to the
foundation of their opinions.
   Notably, the petitioner did not testify at the habeas
trial. Indeed, his habeas experts testified that the peti-
tioner still maintained that he did not commit the crimes
and would become so angry and defensive if any
attempt was made to probe into that matter that they
were forced to rely on his lone account of the crimes
to Borden to make a diagnosis. The petitioner also did
not offer Borden or Phillips as habeas witnesses to
explain whether the transcripts or blood test would
have affected their opinions.
   The habeas court determined that counsel had ren-
dered deficient performance in two respects, but that
neither deficiency had prejudiced the petitioner in light
of the position he had taken regarding his defense. The
court deemed McWhirter and Kelly to have performed
deficiently for failing to discover the 1966 transcripts
containing the petitioner’s firsthand account of his
father’s death. The court found that although defense
counsel first became aware of the transcripts when
the state’s attorney raised them while cross-examining
Borden at the second penalty phase, the transcripts
had been available to counsel in materials set aside as
relevant to the 1987 crimes in the state’s attorney’s
office. As to the significance of this evidence, the court
agreed with defense counsel’s assessment that the prior
homicide was in part a ‘‘ ‘wild card,’ ’’ insofar as the
prosecution could benefit from evidence that the peti-
tioner had previously killed someone. The court found
that the balance weighed in favor of full investigation,
however, because the crimes had substantial similari-
ties (irrationally slaying an immediate family member),
and the circumstances of the 1966 crime (suspended
sentence and probation on a charge of manslaughter)
suggested a bona fide defense.
   Nonetheless, the court determined that the petitioner
had not established prejudice because there was not a
reasonable probability that the result would have been
different had this evidence been available. The court
found that ‘‘the petitioner was a difficult and opposi-
tional client who maintained, despite strong evidence
to the contrary, that he did not commit the killings.
Although first trial counsel thought their best defense
was extreme emotional disturbance, because it would
reduce murder to manslaughter and thereby eliminate
a possible death sentence, for this defense to succeed
the petitioner would have to acknowledge his actions
in causing the victims’ deaths. The petitioner would not
make that acknowledgment.’’ (Footnote omitted.) Not
only that, but the petitioner had specifically forbidden
counsel to assert a defense on this basis.
   The court noted that criminal trial counsel had repeat-
edly attempted to change the petitioner’s mind, and
that attempting to override his decision was risky as a
general proposition and particularly so in the present
case. The court noted that it would be difficult to pre-
sent the defense without the petitioner’s testimony
admitting to the killings. There was nothing that would
indicate that the petitioner would be willing to do so,
whereas counsel had expressed a legitimate concern
that the petitioner would take the stand and deny the
killings. That action might not only negate the extreme
emotional disturbance defense, but also would allow
the state to impeach the petitioner with his prior admis-
sion to Borden. As such, the court reasoned that overrid-
ing the petitioner’s decision might not only doom the
effect of the evidence at the guilt phase, but also nega-
tively impact the jurors’ perceptions for purposes of
the penalty phase.
    The habeas court also found counsel deficient for
failing to test the blood sample for evidence of intoxica-
tion. The court could perceive of no strategic reason
not to test the sample given the petitioner’s drug abuse
and the possibility that drug use could support a claim
of intoxication or be a mitigating factor at the penalty
phase, and counsel had provided none. The court agreed
with the petitioner that a blood test for drugs is the
‘‘ ‘gold standard.’ ’’
  Nonetheless, the court found that the petitioner was
not prejudiced by counsel’s failure to test the sample
because he would not have permitted counsel to proffer
that evidence. The court reasoned: ‘‘At the guilt phase,
the assertion of intoxication evidence essentially repre-
sented a concession by the petitioner that, although he
was intoxicated at the time, he nonetheless committed
the killings. . . . The court credits the testimony of
McWhirter that the petitioner refused to allow first trial
counsel to take this approach. Drug testing . . . would
not likely have changed the petitioner’s mind; the peti-
tioner knew that his attorneys had abundant nonscien-
tific evidence of the petitioner’s drug and alcohol abuse,
yet he still opposed presenting evidence of intoxica-
tion.’’ In its discussion of the penalty phase, the court
also found that the petitioner’s habeas experts had not
established that the petitioner took an intoxicating dose
at the critical time before the murders, but rather had
relied on one uncertainty after another.
   In light of its resolution of the aforementioned claims,
the habeas court summarily rejected the petitioner’s
remaining claims of ineffective assistance of guilt phase
counsel, a Brady violation, and cumulative error. The
court deemed the petitioner’s stand regarding his
unwillingness to admit to the killings to preclude a claim
that counsel was ineffective for presenting a marginal
reasonable doubt defense to the exclusion of a meritori-
ous extreme emotional disturbance defense. The court
concluded that the state had not suppressed the 1966
transcripts, but even if it had, the petitioner’s Brady
claim would fail because the materiality standard set
forth in Brady is the same as the prejudice component
of the ineffective assistance of counsel standard. As to
cumulative error, whether framed as ineffective assis-
tance of counsel or due process, the habeas court con-
cluded that such a claim is not cognizable under
Connecticut appellate case law.
  Finally, the court rejected the petitioner’s claim that
he had received ineffective assistance of counsel in
connection with his petition for a new trial.9 The court
concluded that, because there is no statutory or consti-
tutional right to counsel in connection with a petition
for a new trial, the petitioner had no right to effective
assistance of counsel. Accordingly, the habeas court
denied the petitioner’s amended petition for a writ of
habeas corpus. This appeal followed.
                            III
                        APPEAL
   The petitioner challenges the habeas court’s factual
finding that he rejected the presentation of evidence of
intoxication and the court’s legal conclusions as to all
of his claims. In reviewing these claims, we are mindful
that ‘‘[t]he habeas court is afforded broad discretion in
making its factual findings, and those findings will not
be disturbed unless they are clearly erroneous. . . .
The application of the habeas court’s factual findings
to the pertinent legal standard, however, presents a
mixed question of law and fact, which is subject to
plenary review.’’ (Internal quotation marks omitted.)
Horn v. Commissioner of Correction, 321 Conn. 767,
775, 138 A.3d 908 (2016).
                           A
 Ineffective Assistance of Counsel at the Guilt Phase
   A fundamental premise of the petitioner’s challenge
to the habeas court’s decision is that neither his state-
ments rejecting a defense of extreme emotional distur-
bance nor his refusal to admit that he committed the
crimes precludes relief. Citing Wiggins v. Smith, 539
U.S. 510, 123 S. Ct. 2527, 156 L. Ed. 2d 471 (2003), the
petitioner contends that because guilt phase counsel
failed to undertake a reasonable investigation, which
would have uncovered the 1966 transcripts and
included testing the blood sample, neither counsel nor
the petitioner were able to make an informed strategic
choice as to how to proceed. The petitioner asserts that
his refusal to mount an extreme emotional disturbance
defense was limited to the only theory that counsel had
investigated and were prepared to present, namely, that
he had a mixed personality disorder that caused him to
be depressed and pathologically jealous. The petitioner
contends that this defense simply described his state
of mind, whereas a defense based on PTSD and intoxi-
cation would have explained the cause of his violent
conduct. Finally, he contends that his testimony would
not have been required to advance an extreme emo-
tional disturbance defense, and even if he had insisted
upon denying that he had committed the crimes, that
action could have reinforced a defense based on an
impaired mental state.
   The respondent challenges the habeas court’s conclu-
sions that guilt phase counsel’s performance was defi-
cient with regard to either the transcripts or the blood
sample. In addition to arguing that there were valid
tactical reasons for defense counsel’s inaction as to
those two matters, the respondent argues that PTSD is
simply a new diagnosis by new experts based on the
same information on which the criminal trial experts
based their opinions, which establishes neither defi-
cient performance nor prejudice. The respondent
defends the habeas court’s determination that the peti-
tioner’s actions preclude him from establishing the prej-
udice necessary to obtain habeas relief. He further
argues that Schriro v. Landrigan, 550 U.S. 465, 127
S. Ct. 1933, 167 L. Ed. 2d 836 (2007), forecloses the
petitioner’s argument that his actions were immaterial
in the absence of an informed, knowing and voluntary
waiver of the specific evidence that he now claims
should have been presented.
  We limit our analysis to the question of prejudice, as
that issue is dispositive. We conclude that a client’s
resolute, unambiguous instruction not to present miti-
gating evidence, if made knowingly and voluntarily, can
preclude a showing of prejudice from counsel’s failure
to investigate mitigating evidence. We further conclude,
largely for the reasons set forth by the habeas court,
that this standard was met in the present case.
   The petitioner’s challenges to the effectiveness of
counsel are governed by certain well settled principles.
‘‘To succeed on a claim of ineffective assistance of
counsel, a habeas petitioner must satisfy the two-
pronged test articulated in Strickland v. Washington,
466 U.S. 668, 687, 104 S. Ct. 2052, 80 L. Ed. 2d 674
(1984). Strickland requires that a petitioner satisfy both
a performance prong and a prejudice prong. To satisfy
the performance prong, a claimant must demonstrate
that counsel made errors so serious that counsel was
not functioning as the counsel guaranteed . . . by the
[s]ixth [a]mendment. [Id.] To satisfy the prejudice
prong, a claimant must demonstrate that there is a rea-
sonable probability that, but for counsel’s unprofes-
sional errors, the result of the proceeding would have
been different. Id., 694.’’ (Internal quotation marks omit-
ted.) Small v. Commissioner of Correction, 286 Conn.
707, 712–13, 946 A.2d 1203, cert. denied sub nom. Small
v. Lantz, 555 U.S. 975, 129 S. Ct. 481, 172 L. Ed. 2d 336
(2008). Although a petitioner can succeed only if he
satisfies both prongs, a reviewing court can find against
a petitioner on either ground. See id., 713; see also
Strickland v. Washington, supra, 697 (court need not
determine whether counsel’s performance was defi-
cient before examining prejudice suffered by
defendant).
   ‘‘[S]trategic choices made after less than complete
investigation are reasonable precisely to the extent that
reasonable professional judgments support the limita-
tions on investigation. In other words, counsel has a
duty to make reasonable investigations or to make a
reasonable decision that makes particular investiga-
tions unnecessary.’’ Strickland v. Washington, supra,
466 U.S. 690–91. Thus, in Wiggins v. Smith, supra, 539
U.S. 524–28, on which the petitioner relies, the United
States Supreme Court held that although defense coun-
sel was aware of certain aspects of the defendant’s
background, counsel’s failure to compile a complete
social history of the defendant was objectively unrea-
sonable and, thus, counsel rendered deficient perfor-
mance by failing to make a fully informed decision when
deciding against presenting such mitigation evidence.
    The Supreme Court has recognized, however, that
‘‘[t]he reasonableness of counsel’s actions may be deter-
mined or substantially influenced by the defendant’s
own statements or actions. Counsel’s actions are usu-
ally based, quite properly, on informed strategic choices
made by the defendant and on information supplied by
the defendant. In particular, what investigation deci-
sions are reasonable depends critically on such informa-
tion.’’ Strickland v. Washington, supra, 466 U.S. 691.
Nonetheless, a defendant’s refusal to assist in dis-
covering certain evidence does not relieve counsel of
his or her obligation to investigate and seek such evi-
dence from other sources. See Rompilla v. Beard, 545
U.S. 374, 377, 125 S. Ct. 2456, 162 L. Ed. 2d 360 (2005)
(counsel’s decision not to review court file of defen-
dant’s prior convictions that counsel knew prosecution
would probably rely on as evidence of aggravation and
that revealed mitigating evidence, was objectively
unreasonable ‘‘even when a capital defendant’s family
members and the defendant himself have suggested that
no mitigating evidence is available’’).
   Although the foregoing considerations are familiar
to this court, we have not previously considered how
these general principles apply when a defendant has
refused to allow counsel to present mitigating evidence,
and has even gone so far as to suggest that he would
attempt to derail the presentation of such evidence if
pressed. Other courts have confronted this situation,
albeit principally in the context of the penalty phase of
capital cases. Those courts have recognized that when
a defendant instructs counsel not to investigate or pre-
sent mitigating evidence, the scope of counsel’s duty
to investigate may be more limited. Cummings v. Secre-
tary for the Dept. of Corrections, 588 F.3d 1331, 1358–59
(11th Cir. 2009), cert. denied sub nom. Cummings-El
v. McNeil, 562 U.S. 872, 131 S. Ct. 173, 178 L. Ed. 2d
103 (2010); see also Jeffries v. Blodgett, 5 F.3d 1180,
1198 (9th Cir. 1993) (‘‘[C]ounsel’s acquiescence in [the
defendant’s] decision did not constitute deficient per-
formance. Although the [A.B.A., Standards for Criminal
Justice (2d Ed. 1980)] offers some support to [the defen-
dant’s] contention that his counsel should have pre-
sented evidence in mitigation despite his client’s wishes
to the contrary, [those standards] serve only as a guide
for determining whether an attorney’s performance is
adequate.’’ [Internal quotation marks omitted.]), cert.
denied, 510 U.S. 1191, 114 S. Ct. 1294, 127 L. Ed. 2d
647 (1994). ‘‘This does not mean that a defendant’s
instructions as to investigation or presentation of miti-
gating evidence should be ‘blindly followed’ where the
defendant has a possible mental impairment or the
defendant’s instructions are not explicit or are less than
clear.’’ Cummings v. Secretary for the Dept. of Correc-
tions, supra, 1358. ‘‘The reason lawyers may not blindly
follow such commands is that although the decision
whether to use such evidence is for the client, the lawyer
must first evaluate potential avenues and advise the
client of those offering potential merit.’’ (Internal quota-
tion marks omitted.) Adams v. Quarterman, 324 Fed.
Appx. 340, 347 (5th Cir. 2009).
  ‘‘A competent defendant’s clear instruction not to
investigate or present mitigation evidence also impacts
the prejudice prong of the ineffective assistance test.’’
Cummings v. Secretary for the Dept. of Corrections,
supra, 588 F.3d 1359. In Schriro v. Landrigan, supra,
550 U.S. 469–70, the United States Supreme Court con-
fronted a situation in which the defendant, Jeffrey Lan-
drigan, had actively interfered with counsel’s efforts to
elicit mitigating evidence from two witnesses whose
testimony defense counsel sought to present, Landri-
gan’s former wife and his birth mother. Upon ques-
tioning by the trial court, Landrigan affirmed that he had
instructed his counsel not to present ‘‘ ‘any’ ’’ mitigating
evidence. Id., 469. At the conclusion of the sentencing
hearing, when Landrigan was permitted to speak, he
‘‘made a brief statement that concluded, ‘I think if you
want to give me the death penalty, just bring it right
on. I’m ready for it.’ ’’ Id., 470. Landrigan thereafter
sought habeas relief on the ground that his counsel
should have investigated the ‘‘ ‘biological component’ ’’
of his violent behavior resulting from his mother’s use
of drugs and alcohol while pregnant with him and from
family history. Id., 471. A closely divided Supreme Court
held that the defendant was not entitled to an eviden-
tiary hearing on his claim of ineffective assistance
because, in light of Landrigan’s instruction and conduct,
counsel’s failure to investigate further could not have
been prejudicial under Strickland. Id., 475.
   The court explained that ‘‘[n]either Wiggins nor
Strickland addresses a situation in which a client inter-
feres with counsel’s efforts to present mitigating evi-
dence to a sentencing court. Wiggins [v. Smith, supra,
539 U.S. 523] (‘[w]e focus on whether the investigation
supporting counsel’s decision not to introduce mitigat-
ing evidence of [the defendant’s] background was itself
reasonable’ . . .). Indeed, we have never addressed a
situation like this. In Rompilla v. Beard, [supra, 545
U.S. 381] . . . the defendant refused to assist in the
development of a mitigation case, but did not inform
the court that he did not want mitigating evidence pre-
sented.’’ (Emphasis in original.) Schriro v. Landrigan,
supra, 550 U.S. 478.
   The majority rejected, in turn, the reasons cited by
the United States Court of Appeals for the Ninth Circuit
in support of its conclusion that Landrigan was entitled
to an evidentiary hearing to establish ineffective assis-
tance. The majority first rejected the Ninth Circuit’s
primary determination that Landrigan could not have
intended to preclude all mitigating evidence, even that
about which he could not have known due to counsel’s
failure to investigate. Id., 476. The majority concluded
that much of the evidence that Landrigan claimed
should have been investigated overlapped with the evi-
dence that counsel had sought to present. Id. The major-
ity noted that counsel had attempted to call Landrigan’s
birth mother to testify about her ‘‘ ‘drug us[e] during
her pregnancy’ . . . and the possible effects of such
drug use.’’ (Citation omitted.) Id. The majority also
pointed to Landrigan’s disruptive conduct when counsel
tried to proffer anything that could have been consid-
ered mitigating as clear evidence ‘‘that Landrigan would
have undermined the presentation of any mitigating
evidence that his attorney might have uncovered.’’ Id.,
477. The majority did not directly respond to the four
dissenting justices’ criticism that it had not addressed
the lack of neuropsychological information available to
Landrigan at the time of his purported waiver, which
could have established that Landrigan suffered from
an organic brain disorder. Id., 482, 489 (Stevens, J.,
dissenting). The dissent argued that even if Landrigan
knew all of the facts in his history that had led to this
diagnosis, the court could not ‘‘assume that he could
understand their consequences the way an expert psy-
chologist could.’’ Id., 491 (Stevens, J., dissenting).
   The majority, however, did respond to the Ninth Cir-
cuit’s decision to grant relief on the grounds ‘‘that the
record does not indicate that Landrigan’s decision not
to present mitigating evidence was ‘informed and know-
ing’ . . . and that ‘[t]he trial court’s dialogue with Lan-
drigan tells us little about his understanding of the
consequences of his decision . . . .’ ’’ (Citations omit-
ted.) Id., 478–79. The court explained: ‘‘We have never
imposed an ‘informed and knowing’ requirement upon
a defendant’s decision not to introduce evidence. Cf.,
e.g., Iowa v. Tovar, 541 U.S. 77, 88 [124 S. Ct. 1379, 158
L. Ed. 2d 209] (2004) (explaining that waiver of the
right to counsel must be knowing and intelligent). Even
assuming, however, that an ‘informed and knowing’
requirement exists in this case, Landrigan cannot bene-
fit from it, for three reasons.
   ‘‘First, Landrigan never presented this claim to the
Arizona courts. . . . Second, in Landrigan’s presence,
his counsel told the sentencing court that he had care-
fully explained to Landrigan the importance of mitigat-
ing evidence, ‘especially concerning the fact that the
[s]tate is seeking the death penalty.’ . . . Counsel also
told the court that he had explained to Landrigan that as
counsel, he had a duty to disclose ‘any and all mitigating
factors . . . to th[e] [c]ourt for consideration regard-
ing the sentencing.’ . . . In light of Landrigan’s demon-
strated propensity for interjecting himself into the
proceedings, it is doubtful that Landrigan would have
sat idly by while his counsel lied about having pre-
viously discussed these issues with him. And as Landri-
gan’s counsel conceded at oral argument before this
[c]ourt, we have never required a specific colloquy to
ensure that a defendant knowingly and intelligently
refused to present mitigating evidence. . . . Third, the
Court of Appeals overlooked Landrigan’s final state-
ment to the sentencing court: ‘I think if you want to
give me the death penalty, just bring it right on. I’m
ready for it.’ . . . It is apparent from this statement
that Landrigan clearly understood the consequences of
telling the judge that, ‘as far as [he was] concerned,’
there were no mitigating circumstances of which she
should be aware.’’10 (Citations omitted; footnote omit-
ted.) Schriro v. Landrigan, supra, 550 U.S. 479–80.
    In assessing the impact of Schriro on the present
case, two distinctions from the present case bear noting.
First, Schriro and case law from lower courts on this
subject involve mitigation evidence in the penalty phase
of a capital case, wherein the absence of such evidence
made it exceedingly likely that the defendant would
be sentenced to death. Thus, the eighth amendment
concerns informing the standards imposed in those
cases do not apply to the present case. See, e.g., Hamil-
ton v. Ayers, 583 F.3d 1100, 1113 (9th Cir. 2009)
(‘‘[b]ecause [t]he [c]onstitution prohibits imposition of
the death penalty without adequate consideration of
factors which might evoke mercy . . . [i]t is imperative
that all relevant mitigating information be unearthed for
consideration at the capital sentencing phase’’ [citations
omitted; internal quotation marks omitted]).
   Second, Schriro involved the highly deferential
review of state proceedings under the Antiterrorism
and Effective Death Penalty Act of 1996 (federal act),
Pub. L. No. 104-132, 110 Stat. 1214. Schriro v. Landri-
gan, supra, 550 U.S. 473. Under the federal act, reversal
of a state court’s adjudication is permitted only if that
adjudication ‘‘resulted in a decision that was contrary
to, or involved an unreasonable application of, clearly
established [f]ederal law, as determined by the Supreme
Court of the United States . . . or the relevant state-
court decision was based on an unreasonable determi-
nation of the facts in light of the evidence presented in
the [s]tate court proceeding . . . .’’ (Citations omitted;
internal quotation marks omitted.) Id. Thus, the ques-
tion in Schriro was whether the Supreme Court pre-
viously had held that a defendant’s decision not to
present mitigating evidence must be knowing and vol-
untary, not whether it would so hold if that question
were presented to it. Indeed, the court went on to decide
whether the waiver reasonably could be viewed as
knowing and voluntary if such a standard applied.
Clearly, the four dissenting justices believed that such
a standard previously had been established. Moreover,
although the federal act may preclude a federal court
from overturning a state court’s decision on the ground
that the waiver of mitigation evidence was not informed
and knowing; see, e.g., Cowans v. Bagley, 639 F.3d 241,
246–47 (6th Cir. 2011); that scheme does not constrain
this court’s resolution of that question.
   A survey of case law preceding and postdating
Schriro reveals that most courts have applied some
sort of knowing and voluntary standard, expressly or
implicitly, when evaluating the effect of a defendant’s
refusal to allow the presentation of mitigating evidence
at the capital sentencing phase on either (a) the effec-
tiveness of counsel or (b) the validity of a waiver of
the right to present mitigating evidence.11 See Brawner
v. Epps, 439 Fed. Appx. 396, 402–408 (5th Cir. 2011)
(whether waiver of right to present mitigation case is
knowing and voluntary is component of analysis of
ineffective assistance of counsel claim), cert. denied,
     U.S.     , 132 S. Ct. 2375, 182 L. Ed. 2d 1025 (2012);
Blystone v. Horn, 664 F.3d 397, 423–26 (3d Cir. 2011)
(concluding that state court unreasonably concluded
that facts demonstrated that defendant made ‘‘ ‘know-
ing, intelligent, and voluntary’ waiver of his right to
present any mitigating evidence at sentencing’’ [empha-
sis in original]); Allen v. Secretary, Florida Dept. of
Corrections, 611 F.3d 740, 763–64 (11th Cir. 2010) (not-
ing in review of state court’s decision that Schriro fore-
closed argument that defendant’s waiver of mitigation
case should be deemed invalid because, due to lack
of investigation, counsel failed to inform defendant of
evidence he was giving up, but nonetheless explaining
why waiver was knowing and intelligent), cert. denied
sub nom. Allen v. Buss, 563 U.S. 976, 131 S. Ct. 2898,
179 L. Ed. 2d 1192 (2011); Hamilton v. Ayers, supra,
583 F.3d 1118–19 (defendant’s decision not to allow
presentation of mitigating evidence can excuse coun-
sel’s failure to present such evidence when defendant’s
decision is knowing, voluntary, and intelligent);12 Cole-
man v. Mitchell, 268 F.3d 417, 447–49 (6th Cir. 2001)
(counsel’s effectiveness in connection with defendant’s
instruction not to present mitigating evidence deter-
mined in light of whether defendant’s decision was
knowing and informed); Battenfield v. Gibson, 236 F.3d
1215, 1231–34 (10th Cir. 2001) (counsel rendered inef-
fective assistance in failing to conduct adequate investi-
gation despite defendant’s instruction not to present
any mitigating evidence because waiver was not know-
ing and intelligent); Chandler v. Greene, Docket No. 97-
27, 1998 WL 279344, *8 (4th Cir. May 20, 1998) (affirming
district court’s conclusion that counsel was not ineffec-
tive for following defendant’s knowing and voluntary
decision to forgo presentation of mitigating evidence
to jury) (decision without published opinion, 145 F.3d
1323 [4th Cir. 1998]), cert. denied, 524 U.S. 974, 119 S.
Ct. 23, 141 L. Ed. 2d 783 (1998); Emerson v. Gramley,
91 F.3d 898, 906–907 (7th Cir. 1996) (defendant’s waiver
of right to present mitigating evidence was not knowing
waiver to which he could be held in light of counsel’s
failure to conduct any investigation into mitigating evi-
dence), cert. denied sub nom. Emerson v. Gilmore, 520
U.S. 1122, 117 S. Ct. 1260, 137 L. Ed. 2d 339 (1997), cert.
denied sub nom. Gilmore v. Emerson, 520 U.S. 1139, 117
S. Ct. 1289, 137 L. Ed. 2d 364 (1997); Snell v. Lockhart,
14 F.3d 1289, 1302–1303 (8th Cir.) (defendant validly
waived right to present mitigating evidence because
choice was informed, voluntary, and intelligent), cert.
denied sub nom. Snell v. Norris, 513 U.S. 960, 115 S. Ct.
419, 130 L. Ed. 2d 334 (1994); see also Commonwealth v.
Rega, 593 Pa. 659, 711, 933 A.2d 997 (2007) (‘‘[C]ertain
jurisdictions require capital counsel to conduct an
investigation into potential mitigation evidence to
ensure that a defendant’s waiver of such proof is know-
ing and intelligent. . . . Pennsylvania, however, aligns
with those states that do not so require, demanding
only that the defendant’s waiver be knowing, intelligent,
and voluntary.’’ [Citation omitted.]), cert. denied, 552
U.S. 1316, 128 S. Ct. 1879, 170 L. Ed. 2d 755 (2008).
    Precisely what such a standard requires appears to
be context specific. Certain common factors can be
gleaned from the jurisdictions that have applied this
standard, however, which are consistent with those
that Schriro indicated would apply if a knowing and
intelligent waiver of mitigating evidence was constitu-
tionally required. The record must establish that the
defendant clearly and unequivocally expressed an inten-
tion not to present any mitigating evidence (or to limit
the mitigation evidence). See Schriro v. Landrigan,
supra, 550 U.S. 475–76; Blystone v. Horn, supra, 664
F.3d 425–26 (concluding that defendant’s statement
declining to ‘‘ ‘offer any other evidence’ ’’ did not sug-
gest that defendant intended to preclude all mitigation
evidence when read in context and when record estab-
lished no basis to conclude that counsel had discussed
mitigation evidence other than through testimony of
defendant and his parents); Loden v. McCarty, 778 F.3d
484, 498–500 (5th Cir.) (record established ‘‘firm,’’ ‘‘con-
sidered,’’ ‘‘resolute’’ decision not to present any mitiga-
tion evidence), cert. denied sub nom. Loden v. Fisher,
      U.S.     , 136 S. Ct. 402, 193 L. Ed. 2d 315 (2015);
Young v. Sirmons, 551 F.3d 942, 959 (10th Cir. 2008)
(‘‘[W]e find it impossible to predict with any degree of
certainty what [the defendant] would have done had
his trial counsel investigated and prepared to present all
of the available mitigating evidence that [the defendant]
now points to. In particular, we do not believe that [his]
decision to [forgo] the live testimony of his friends and
family members allows us to accurately predict what
he would have done had his trial counsel planned to
present mitigating testimony from [certain experts].’’),
cert. denied, 558 U.S. 906, 130 S. Ct. 272, 175 L. Ed. 2d
183 (2009).
   The record must also reflect that the defendant under-
stood that he had the right to present mitigating evi-
dence, the nature of the mitigating evidence, and the
consequences of failing to present such evidence.
Schriro v. Landrigan, supra, 550 U.S. 479–80; see also
Coleman v. Mitchell, supra, 268 F.3d 447 (defendant
must know ‘‘meaning of mitigation evidence and the
availability of possible mitigation strategies’’ and have
‘‘understanding of competing mitigation strategies’’
[internal quotation marks omitted]); Battenfield v. Gib-
son, supra, 236 F.3d 1230–31 (waiver was not valid
when petitioner instructed as to right but did not have
understanding of general nature of mitigating evidence
or specific types of mitigation evidence that might be
available). This does not mean that the defendant must
be fully informed about the specifics of the mitigation
evidence. A higher standard would be inconsistent with
Schriro and the United States Supreme Court’s waiver
jurisprudence generally. See United States v. Ruiz, 536
U.S. 622, 629, 122 S. Ct. 2450, 153 L. Ed. 2d 586 (2002)
(‘‘the law ordinarily considers a waiver knowing, intelli-
gent, and sufficiently aware if the defendant fully under-
stands the nature of the right and how it would likely
apply in general in the circumstances—even though the
defendant may not know the specific detailed conse-
quences of invoking it’’ [emphasis omitted]); see also
United States v. Demeke, Docket No. 96-1413, 1998 WL
391051, *2 (2d Cir. May 20, 1998) (rejecting argument
that district court had obligation to conduct full inquiry
into applicability of diminished capacity defense to cir-
cumstances of case before allowing defendant to forgo
defense in contravention to advice of counsel) (decision
without published opinion, 152 F.3d 921 [2d Cir. 1998]).
  Finally, although Schriro did not expressly address
this concern, there is consensus that counsel may not
acquiesce to such an instruction when there is evidence
the defendant is not competent to make such a decision.
See, e.g., Brawner v. Epps, supra, 439 Fed. Appx. 408;
Allen v. Secretary, Florida Dept. of Corrections, supra,
611 F.3d 764–65; Cummings v. Secretary for the Dept.
of Corrections, supra, 588 F.3d 1358–59; Chandler v.
Greene, supra, 1998 WL 279344, *8; Snell v. Lockhart,
supra, 14 F.3d 1303.
   Accordingly, we agree with the United States Court
of Appeals for the Eleventh Circuit that, if the record
establishes that the petitioner made a knowing and
intelligent decision not to present mitigating evidence
under the general factors previously discussed, he must
make two showings to establish prejudice under Strick-
land. First, the petitioner must show that if he had been
advised more fully about the mitigating evidence, there
is a reasonable probability he would have permitted trial
counsel to present such evidence at trial. See Gilreath v.
Head, 234 F.3d 547, 551 (11th Cir. 2000), cert. denied,
534 U.S. 913, 122 S. Ct. 255, 151 L. Ed. 2d 186 (2001);
see also Cummings v. Secretary for the Dept. of Correc-
tions, supra, 588 F.3d 1360 (‘‘there cannot be a reason-
able probability of a different result if the defendant
would have refused to permit the introduction of miti-
gating evidence in any event’’). Second, the petitioner
must establish that, if such evidence had been pre-
sented, a reasonable probability exists that the result
would have been different. Cummings v. Secretary for
the Dept. of Corrections, supra, 1365–66. With these
standards in mind, we turn to the petitioner’s claims.
                            1
 Failure to Discover Transcripts to Establish PTSD
  The petitioner claims that he was prejudiced by
defense counsel’s failure to discover the 1966 tran-
scripts because they deprived him of evidence that
would have led to a diagnosis that he was under an
extreme emotional disturbance caused by PTSD at the
time of the crimes. According to the petitioner, the
transcripts revealed that he was in a dissociative state
when he killed his father, which would have led to a
diagnosis that he suffered from PTSD with dissociative
features when he killed his former wife and his son.
The petitioner argues that such a diagnosis would have
presented a different basis for an extreme emotional
disturbance defense than the severe mixed personality
disorder diagnosed by the criminal trial experts, which
effectively portrayed him as a pathologically jealous
former husband, as it would explain his violent reaction
to stressful circumstances. We conclude that, even if
we were to assume that guilt phase counsel were defi-
cient for failing to discover the transcripts, any such
deficiency did not prejudice the petitioner.
   Although the habeas court emphasized the fact that
the petitioner would not agree to testify in support of
an extreme emotional disturbance defense and might
even insist on testifying to dispute that he had commit-
ted the crimes, our conclusion rests on a broader view
of the record consistent with our previous discussion
of the law.13 The record provides ample proof that the
petitioner had consistently and unequivocally taken the
position that he would not allow counsel to present
any mitigating evidence that was tantamount to an
admission that he had committed the crimes, but lacked
the intent to kill when he did so. The sole statements
to the contrary came shortly after his arrest, between
January 11 and February 20, 1988. Don Light, a defense
investigator, noted that when he questioned the peti-
tioner about his sister’s report that he was having night-
mares and flashbacks, the petitioner ‘‘became cheerful
and made vague statements, such as, if I did it, I can’t
believe that I did. He also said is it possible that I could
have done this and not be aware that I did so.’’ Weeks
later, the petitioner provided a detailed confession in
his first interview with Borden, in the presence of Light
and Kelly.
   From March, 1988 until the defense rested in April,
1989, the petitioner, however, vehemently denied that
account. When Borden met with the petitioner for the
second time in March, 1988, two weeks after he had
confessed to the crimes, the petitioner not only refused
to discuss the events on the night of the murders but
denied having committed the crimes. When Borden con-
fronted him with his prior confession, the petitioner
acknowledged the statement but said that he had made
it up. He continued to maintain that he had not commit-
ted the crimes in subsequent interviews with Borden
in September and December, 1988. Similarly, Phillips
noted that, in her October, 1988 psychological evalua-
tion, the petitioner insisted that he had no direct knowl-
edge of the manner of the victims’ deaths. In her report,
Phillips further noted that, ‘‘[a]lthough he strongly
denied knowledge of his family’s murder, [the peti-
tioner] stated that ‘I told them I did it . . . they needed
somebody . . . I had no reason not to tell them . . .
I have no reason to go on anymore.’ ’’
   The petitioner also repeatedly expressed a desire to
either force the state to prove its case or to have the
state execute him. In September, 1988, Light reported
to defense counsel that, when he had informed the
petitioner about his upcoming evaluation with Phillips,
the petitioner had said that defense counsel promised
him the best possible defense, that he wanted a trial,
and that he wanted ‘‘the state to ‘have to prove the
case’ so that they can ‘zap me,’ which is ‘what I want.’ ’’
In response to this news, Kelly wrote a letter to the
petitioner stating that Light had reported the petition-
er’s ‘‘expressed desire to have the [state] execute [him],
and the effect of that attitude on the nature of any
defense to be presented.’’ Kelly asked the petitioner to
keep an open mind on his options until defense counsel
had a chance to assess all of the information and present
him with his options.
   At some unspecified point, the petitioner wrote a
letter to Kelly stating in part: ‘‘I have no need of spending
the rest of my life or any large part of it in a prison with
unknown dreams, feelings and [an] uncertain knowing
guilt. So my need is not to settle for anything lesser
than the electric chair and without appeal which in turn
will cause my death. For that’s the least I can do. I can’t
feel or think of any other way!’’
   In her October, 1988 psychological evaluation, Phil-
lips noted that the petitioner had said that ‘‘ ‘it’s not
worth trying to restart a life.’ ’’ The petitioner
‘‘expressed skepticism about his attorneys, doubting
their commitment to helping him. He described the legal
proceedings as a ‘game’ and stated that he was now
only interested in seeing how ‘the system is—how good
or bad it is—how the game is played.’ ’’
   Sometime between the end of December, 1988 and
the beginning of January, 1989, the petitioner rejected
a plea bargain under which he would have avoided a
death sentence but would have had to spend the rest
of his life in prison. In a January, 1989 letter to the
petitioner, defense counsel memorialized the two alter-
natives that the petitioner had rejected, one of which
would have allowed him to enter an Alford plea14 of
guilty to two counts of murder. To ensure that the
petitioner understood what this meant, the letter
explained that an Alford plea would simply acknowl-
edge that the state had sufficient evidence that, if
believed by a jury, would likely establish his guilt, and
would not be an admission that the petitioner had com-
mitted the crimes. The letter noted that counsel thought
it was important to make this clear ‘‘[i]n light of the
different positions you have taken with us at various
times throughout the course of our representation (‘I
didn’t do it’/‘I did it’/‘Maybe I did it’/‘I don’t remem-
ber’) . . . .’’
   In that letter, defense counsel also recounted prior
discussions with the petitioner regarding the fact that
Borden’s psychiatric evaluation gave them a potential
extreme emotional disturbance defense. The letter
explained that, if credited, extreme emotional distur-
bance would be a complete defense to capital felony,
and would reduce the two murder counts to manslaugh-
ter in the first degree, which would likely result in
maximum, consecutive sentences for a term of forty
years imprisonment. It went on to note: ‘‘Despite the
fact that an [extreme emotional disturbance] defense
could, if successful, significantly reduce any penalty,
you have forbidden us to use such a defense. We advised
you before you made that decision that, in our opinion,
defending the charges on an [extreme emotional distur-
bance] theory was the best way to go. Given your posi-
tion on [extreme emotional disturbance], we will
proceed accordingly, not because we agree that it is
the best way to go, but because you, as the client have
the power to make that decision, even if we feel it is
not in your best interests. You should be aware, how-
ever, that we, therefore, will not file any Notice of Inten-
tion to Rely (on any kind of mental defense) as we are
required to by law . . . .’’ The letter ended by advising
the petitioner to inform counsel immediately if they
had misunderstood his position with regard to rejecting
the plea bargain or an extreme emotional disturbance
defense. There is no evidence that the petitioner there-
after contacted counsel to indicate that they had misun-
derstood his position.
   As noted in part I of this opinion, because of their
concerns about the petitioner’s statements and his
rejection of their advice, defense counsel requested a
competency evaluation in January, 1989. The evaluation
noted that the petitioner ‘‘reported [that] his attorneys
have discussed with him the possible defenses avail-
able. . . . He indicate[d] that he differs with his attor-
neys in his assessment of the strength of the evidence
against him. He reports he is presently determined to
take his case to trial, believing that the prosecution
will have great difficulty proving his guilt ‘beyond a
reasonable doubt’ to a jury.’’ Following the clinical
team’s report to the court, two separate colloquies
ensued with the petitioner. At each, the trial court con-
firmed with the petitioner that he had directed counsel
not to present a defense of extreme emotional distur-
bance or ‘‘any psychiatric testimony,’’ and that he under-
stood that he was forgoing the possibility of a strategy
that could avoid a death sentence and life impris-
onment.
   At the habeas trial, McWhirter testified that the peti-
tioner had been adamant about not presenting evidence
of extreme emotional disturbance at the guilt phase.
McWhirter affirmed that he had explained to the peti-
tioner ‘‘the risk of pursuing the reasonable doubt
defense instead of [extreme emotional disturbance] or
other mental state defense.’’ McWhirter stated that, in
light of the petitioner’s position, their defense strategy
was ‘‘to make the state cross all the ‘T’s, dot all the ‘I’s,
and prove the case beyond a reasonable doubt.’’
   With respect to specifically using PTSD as the basis
for an extreme emotional disturbance defense,
McWhirter stated that he was sure that they had consid-
ered that condition, by that name or in another form.
McWhirter had always assumed that the petitioner was
in a dissociative state when he committed the murders.
Although the petitioner was never specifically diag-
nosed with PTSD, McWhirter knew that the petitioner
had traumatic events in his background that he thought
had impacted the petitioner’s mental state.
   Kelly could not recall discussing PTSD with the peti-
tioner, but explained that they had not considered rely-
ing on PTSD as an affirmative defense at the guilt phase
‘‘because as with [extreme emotional disturbance] we
were faced with a certain dilemma and that dilemma
was that [the petitioner], in effect, had indicated that
if we tried to offer a defense that necessarily involved
him having done the act of killing his family, that he
would insist upon testifying and denying it. Thereby,
in my view, making him not only a murderer, if the jury
should so find, but someone capable of looking them
in the face and being—and—and lying to them and
being a liar on top of it, which then would have implica-
tions for the penalty phase.’’
   This evidence conclusively demonstrates that the
petitioner was informed, by the court and by counsel,
that mitigation evidence could be presented that could
reduce his culpability, and was advised against proceed-
ing on a theory of reasonable doubt that had little
chance of success. The court found the petitioner com-
petent to make this decision, a finding that was sup-
ported by the opinion of an independent panel. That
his decision made it more likely that he would be
exposed to a death sentence rather than a lengthy sen-
tence of imprisonment does not in and of itself contra-
vene that finding.15 The petitioner did not expressly
limit or in any way qualify the scope of his decision to
any particular extreme emotional disturbance theory or
type of psychiatric testimony. Nor is there any evidence
from which such a limitation may be inferred.
  From his second meeting with Borden in March, 1988
until the defense rested at the guilt phase in April, 1989,
the petitioner consistently refused to undertake any
course of action that would be tantamount to an admis-
sion to having committed the crimes and insisted on
forcing the state to prove its case beyond a reasonable
doubt. The petitioner effectively took the position that
the only acceptable outcome would be an acquittal or
a death sentence. In either case, an extreme emotional
disturbance defense, whether based on PTSD or other
mental conditions, would thwart that clear intention.
   The mere fact that defense counsel never specifically
discussed PTSD by its name and diagnostic features
with the petitioner does not support a conclusion that a
reasonable possibility existed that the petitioner would
have allowed counsel to advance a defense based on
PTSD if counsel had informed him that there was evi-
dence to support such a theory. Defense counsel’s
investigation in support of an extreme emotional distur-
bance defense uncovered many of the same basic facts
essential to the habeas experts’ diagnosis of PTSD with
dissociative features.16 The habeas experts opined that
the petitioner’s PTSD arose from childhood trauma,
events before and including his father’s death. Borden
opined that the severe chronic abuse that the petitioner
had suffered when he was a child was the cause of the
petitioner’s mental disorder and had ‘‘led up to what
happened.’’ He characterized the death of the petition-
er’s father as an event that left a deep emotional scar
and connected it to the 1987 killings. The habeas experts
opined that methamphetamine intoxication would
exacerbate PTSD symptoms of impulsivity and aggres-
sion. Borden reached the same conclusion regarding
the drug’s effects on the condition he had diagnosed,
specifically stating that the drug could trigger violent
behavior.17 Phillips testified that the petitioner’s illness
would significantly reduce his ability to contain his
emotions and rage if confronted with conflict or loss.
The habeas experts opined that the 1966 event placed
the petitioner at greater risk of responding to traumatic
events by developing a dissociative reaction. Borden
and Phillips described the petitioner’s mental condition
as one that could cause a person, when under severe
stress, to ‘‘dissociate,’’ experience ‘‘depersonalization,’’
‘‘derealization,’’ or a ‘‘disoriented state,’’ or go into a
fugue state where one lacks awareness of what he is
experiencing. Borden pointed specifically to the peti-
tioner’s perception that he was not harming the victims
but rather that his hand had committed the harmful
acts. Defense counsel testified that they ‘‘always’’ had
thought that the petitioner was in a dissociative state
attributable to his childhood abuse at the time of the
killings, even though they did not attribute it specifically
to PTSD.
   Indeed, one of the petitioner’s habeas experts who
diagnosed the petitioner with PTSD, Blumberg, testi-
fied: ‘‘I think . . . Borden and I are in the same ballpark
but may have some different diagnostic labels that we’re
using. . . . If you think that what . . . Borden has dis-
cussed in his diagnosis of this mixed personality disor-
der, all these features that he labels are actually features
and symptoms of [PTSD]. . . . I would just really
describe many of these features that he sees as part of
his personality disorder as really being diagnostic of
chronic [PTSD].’’
   We do not intend to suggest that PTSD and severe
mixed personality disorder with the petitioner’s associ-
ated features lack any clinically material distinction.
Nor do we suggest that defenses based on PTSD and
such a disorder would have had equivalent tactical
advantages. Our concern is whether these diagnoses
would have been seen as materially different from the
petitioner’s perspective when deciding to preclude an
extreme emotional disturbance defense or the presenta-
tion of any psychiatric testimony. The record does not
establish that there is a reasonable probability the peti-
tioner would have allowed counsel to present a PTSD
defense if only counsel had discussed PTSD by name,
clinical definition, or symptomology.
   To the extent that the petitioner argues that his deci-
sion was based on an extreme emotional disturbance
defense limited to a theory that the petitioner commit-
ted the crimes because he was a sad, pathologically
jealous man, the scope of the investigation and the
testimony of Borden and Phillips does not support that
limited view. It might be fair to say that the state pressed
such a theory, but those characteristics were only one
part of a far more complex picture of the petitioner’s
mental condition that defense counsel’s investigation
had yielded. Nothing in the record reflects that defense
counsel ever discussed their proposed defense in such
terms with the petitioner. The petitioner declined to
testify on this or any other matter at the habeas trial.
   For the foregoing reasons, the petitioner cannot
establish that he was prejudiced by counsel’s failure to
uncover the 1966 transcripts. In light of his instructions
to counsel and his refusal to assist in the development
and presentation of mitigation evidence, there is not a
reasonable probability of a different outcome if counsel
had uncovered them. Moreover, because methamphet-
amine intoxication was an essential element of the opin-
ions of each of the petitioner’s experts, meaning that
none concluded that PTSD alone caused an extreme
emotional disturbance, the petitioner’s PTSD claim also
fails for the reasons set forth in the next subpart of
this opinion.
                             2
            Failure to Test Blood Sample to
              Establish Methamphetamine
                 (Desoxyn) Intoxication
   The petitioner claims that although the habeas court
properly concluded that counsel was deficient for fail-
ing to test the first blood sample because there was no
strategic reason not to and such a test would have
been the best evidence of intoxication, it improperly
concluded that he was not prejudiced. He contends that
the habeas court’s finding that he rejected a defense
strategy based on intoxication is clearly erroneous. The
petitioner further contends that he could not have made
an informed decision to do so because counsel never
discussed the presentation of intoxication evidence.
We disagree.18
   The record reflects the following additional evidence
related to the intoxication claim. In his February, 1988
confession to Borden, in the presence of Kelly and Light,
the petitioner recounted his alcohol and drug abuse in
the years and months preceding the crimes, citing
‘‘drugs including [V]alium, [F]iorinal and [De]soxyn.’’
In recounting the events in the days leading up to the
murders early Sunday morning, December 13, 1987, the
petitioner indicated that at various times on the preced-
ing Wednesday and Thursday, he had been drinking and
taking pills, including Desoxyn specifically, but could
not remember how many pills. In his account of the
events on Friday, Saturday, and early Sunday morning,
he noted at several points that he had been drinking,
but did not mention taking any pills or drugs.
   Notes dated February, 1988, reflect that Light began
an investigation into the petitioner’s drug use in the
days leading up to the crimes. He obtained a letter from
the physician who had prescribed medications to the
petitioner since 1985, which indicated that the physician
had last prescribed Desoxyn to the petitioner on Decem-
ber 9, 1987 (three full days before the crimes). Light
interviewed the pharmacist who had filled that prescrip-
tion as well as previous prescriptions. The pharmacist
indicated that the petitioner had previously abused his
prescription medication, trying to obtain refills prema-
turely. The pharmacist confirmed that, on December 9,
he had filled the petitioner’s prescriptions for thirty
Desoxyn pills and for 100 Fiorinal pills. Light learned
that Desoxyn is an amphetamine and Fiorinal is a relax-
ant. Light found it ‘‘[n]otable’’ that, although the
Desoxyn prescription specified a dosage of one pill per
day, the petitioner’s sister had informed Light that the
bottle was empty when she found it in the petitioner’s
apartment five days after the prescription had been
filled.19 Light also contacted the petitioner’s health
insurance provider to ascertain when and for what pre-
scriptions it had paid.
   At the habeas trial, McWhirter confirmed that the
petitioner’s use of medications would have been a sub-
ject of inquiry because such use could be relevant to
the petitioner’s state of mind and a possible defense
strategy. Light’s report of his investigation into the peti-
tioner’s prescriptions and the empty prescription bottle
gave McWhirter reason to believe that the petitioner
may have been under the influence of more than his
prescribed level of medication at the time of the mur-
ders. McWhirter testified that the petitioner had told
defense counsel ‘‘from the beginning that he was under
the influence . . . of alcohol and prescription medica-
tions . . . .’’ McWhirter further testified that, although
he had no recollection of the specific inquiry to the
petitioner whether he was using any drugs or alcohol
at the time of the murders, he was ‘‘quite sure that we
had such a discussion at some point.’’ He could not
recall whether the petitioner had informed defense
counsel of the quantity of each drug he had taken before
the murders, but assumed the questions had been asked.
As previously noted, McWhirter explained that the use
of intoxication evidence ‘‘never got raised because [the
petitioner] would not let us go in that direction.’’
   We conclude that the habeas court’s finding that the
petitioner would not allow counsel to present intoxica-
tion evidence is not clearly erroneous. The habeas court
credited McWhirter’s testimony that intoxication had
been discussed with the petitioner and that he would
not allow them ‘‘to take this approach.’’ Insofar as this
is a pure credibility determination, it is unassailable.
See Sanchez v. Commissioner of Correction, 314 Conn.
585, 604, 103 A.3d 954 (2014) (‘‘we must defer to the
[trier of fact’s] assessment of the credibility of the wit-
nesses based on its firsthand observation of their con-
duct, demeanor and attitude’’ [internal quotation marks
omitted]); Taylor v. Commissioner of Correction, 284
Conn. 433, 448, 936 A.2d 611 (2007) (‘‘[t]he habeas judge,
as the trier of facts, is the sole arbiter of the credibility of
witnesses and the weight to be given to their testimony’’
[internal quotation marks omitted]). Indeed, the peti-
tioner offered no evidence to the contrary.
   Granted, this single statement alone would be a thin
reed on which to rest the habeas court’s ultimate find-
ing. The evidence previously discussed, however,
makes clear that this statement was not the only support
for this finding. The evidence established that counsel
had recognized that intoxication evidence could be used
to raise a question as to the petitioner’s ability to form
the necessary specific intent, and had commenced an
investigation into this subject. Defense counsel
obtained information from the physician who pre-
scribed medications to the petitioner, the pharmacist
who filled the prescriptions, the insurance company
who paid for the prescriptions, and a family member
who had knowledge of the petitioner’s usage. From
these sources and the petitioner’s confession, counsel
learned what medications the petitioner actually had
been prescribed shortly before the murders, that he
previously had abused his medications, that he had been
abusing them a few days before the murders, and that
most of his thirty day supply of Desoxyn, received on
December 9, was gone on December 14. The fact that
no further investigation was undertaken would seem
to corroborate that the petitioner had instructed coun-
sel not to ‘‘go in that direction.’’ Indeed, such an instruc-
tion was wholly consistent with the petitioner’s refusal
to allow the presentation of any theory tantamount
to an admission to committing the homicides, and his
expressed desire to make the state prove its case.
   Despite the fact that the two colloquies with the crimi-
nal trial court were limited to the petitioner’s decision
not to present evidence of extreme emotional distur-
bance, we are persuaded that the record establishes
that the petitioner understood the consequences of
refusing to allow evidence of intoxication. Indeed, the
only strategies that he ever embraced prior to the con-
clusion of the guilt phase were to obtain an acquittal
or a sentence of death. A successful presentation of
intoxication evidence would not achieve either end.
Therefore, the petitioner’s instructions to counsel pre-
clude his claim that he was prejudiced by counsel’s
failure to test the blood sample because he has not
established that he would have allowed evidence of
intoxication had such a test been conducted.
   Even if the petitioner could successfully distinguish
a defense strategy based on intoxication from one based
on an extreme emotional disturbance, he still could not
establish the prejudice necessary to prevail on a claim
of ineffective assistance. We agree with the habeas
court that the petitioner did not proffer evidence estab-
lishing a reasonable probability that he ingested an
intoxicating dose of Desoxyn at a point in time prior
to the crimes when it would have materially affected
his conduct during the commission of the crimes.
   Putting aside the habeas court’s questions as to
whether the petitioner’s experts accurately extrapo-
lated from the blood sample a range of the level of
methamphetamine at the time of the blood draw, the
petitioner’s expert, Stewart, conceded that these levels
could be explained by the ingestion of Desoxyn shortly
before the crimes, shortly after the crimes, or some
combination thereof. He admitted that his intoxication
opinion, therefore, relied upon an ‘‘assumption’’ that
the petitioner had ingested the pills before the crimes,
finding support for that assumption in the contrast
between the petitioner’s description of his state of mind
during the crimes and others’ description of his
demeanor in the thirty-six hours afterward. According
to Stewart, the petitioner’s description was consistent
with someone suffering from methamphetamine intoxi-
cation, whereas others’ descriptions were ‘‘consistent’’
or ‘‘not inconsistent’’ with someone coming down from
a methamphetamine high. Stewart admitted on cross-
examination, however, that the petitioner’s demeanor
after the crimes was not inconsistent with someone
suffering methamphetamine intoxication, and that it
was possible for someone to be in such a state without
it being readily apparent. Stewart’s opinion did not
account for the petitioner’s strategic conduct upon leav-
ing the crime scene of washing away any traces of
blood from his person, clothing, and shoes. Moreover,
Stewart’s assumption that a single blood draw could
reliably establish the petitioner’s intoxication at a set
point in time was not only contradicted by the respon-
dent’s toxicology expert, Charles McKay, but also by the
petitioner’s toxicology expert, Gary Lage. Lage testified,
consistent with McKay, that one could not tell from the
level of methamphetamine in a single blood sample how
much of the drug had been taken or when it was taken;
one would need either the dosage or the time of inges-
tion to determine the other element.
   The petitioner’s experts also apparently gave no
weight to the petitioner’s own statements regarding his
drug consumption, which would seem to be the best
evidence of this fact and did not support a theory of
methamphetamine intoxication. The petitioner’s narra-
tive to Borden contained no fewer than eight references
to taking Desoxyn, ‘‘pills,’’ or ‘‘drugs.’’ He specifically
recounted taking Desoxyn or ‘‘pills’’ as well as drinking
at certain times on Wednesday and Thursday before the
murders early Sunday morning. Although he recounted
drinking (and, notably, even when, how many and what
kind of alcoholic drinks he had) on Friday, Saturday,
and the early hours of Sunday just before the murders,
he never mentioned taking any pills during this period.
Approximately thirty-two hours after the murders,
when the petitioner was asked about his current medi-
cations at the emergency room for treatment of his
cut hand, he mentioned Fiorinal but not Desoxyn. The
petitioner’s report to hospital personnel undermines
the petitioner’s argument that little weight should be
assigned to his failure to mention taking Desoxyn in
his account to Borden because no one specifically asked
the petitioner whether he had taken any pills shortly
before the crimes. When asked, he still failed to report
recently taking Desoxyn. Therefore, the petitioner has
not established that there is a reasonable probability
that, had the blood sample been tested, a different result
would have ensued.20
                            3
    Presentation of Reasonable Doubt Defense to
          Exclusion of Extreme Emotional
                Disturbance Defense
  The petitioner argues that, because defense counsel
recognized that a reasonable doubt defense had a mar-
ginal chance of success, they rendered ineffective assis-
tance by failing to present a meritorious extreme
emotional disturbance defense. The petitioner contends
that defense counsel could not accede to the petitioner’s
direction not to assert an extreme emotional distur-
bance defense both because the petitioner’s decision
was uninformed and because it was a tactical decision
for counsel to make. Parts III A 1 and 2 of this opinion
dispose of the petitioner’s first argument. We also dis-
agree with his second argument.
  Numerous courts have held that counsel has an ethi-
cal obligation to comply with an informed defendant’s
refusal to allow presentation of a mental disease or
defect defense or mitigating evidence in the penalty
phase of a capital case. See Frye v. Lee, 235 F.3d 897,
906 (4th Cir. 2000) (‘‘[I]n North Carolina—as in most
jurisdictions—the client must be permitted by his law-
yers to control his own defense, as long as he is fully
informed in making his decisions. . . . Frye’s attor-
neys took reasonable steps to comply with their profes-
sional responsibilities in this regard. Frye’s decision not
to allow his family to aid in mitigation was unchanged
after repeated discussions where his lawyers explained
their displeasure with his position, and the conse-
quences thereof.’’ [Citations omitted; internal quotation
marks omitted.]), cert. denied, 533 U.S. 960, 121 S. Ct.
2614, 150 L. Ed. 2d 769 (2001); Dobbs v. Turpin, 142
F.3d 1383, 1388 (11th Cir. 1998) (‘‘the decision whether
to use mitigating evidence is for the client’’); Adams v.
Quarterman, supra, 324 Fed. Appx. 347 (‘‘although the
decision whether to use [mitigation] evidence is for the
client, the lawyer first must evaluate potential avenues
and advise the client of those offering potential merit’’
[internal quotation marks omitted]); Johnson v. State,
117 Nev. 153, 162 and n.14, 17 P.3d 1008 (2001) (‘‘[t]he
majority of [s]tates honor a competent defendant’s
choice to forgo a defense strategy that asserts, in any
way, that he or she was not guilty of the crime charged
by reason of insanity—even over defense counsel’s
objections’’; [internal quotation marks omitted]; and
collecting cases).
   The logic underlying these decisions extends to a
client’s instruction to his attorney not to present an
extreme emotional disturbance defense. See Petrovich
v. Leonardo, 229 F.3d 384, 386–87 (2d Cir. 2000) (‘‘The
decision to assert an affirmative defense [such as
extreme emotional disturbance] is akin to other, funda-
mental trial decisions, such as the decision to plead to
a lesser charge or to assert a plea of insanity. . . . If
that analogy is sound, a court must accept a defendant’s
will in such matters.’’ [Citations omitted.]), cert. denied,
532 U.S. 981, 121 S. Ct. 1623, 149 L. Ed. 2d 485 (2001);
cf. State v. Jones, 99 Wn. 2d 735, 743, 664 P.2d 1216
(1983) (en banc) (‘‘The stigma of insanity may in some
cases be more damaging. Finally, a defendant may have
legitimate philosophical reasons for opposing entry of
[a not guilty by reason of insanity] plea. He may view
such a plea as a tacit admission of guilt which he does
not wish to make.’’). To conclude otherwise could force
a defendant to represent himself in order to control the
defense that he wishes to present. See, e.g., Godinez
v. Moran, 509 U.S. 389, 392, 113 S. Ct. 2680, 125 L. Ed.
2d 321 (1993) (‘‘[The] respondent informed the court
that he wished to discharge his attorneys and change
his pleas to guilty. The reason for the request, according
to [the] respondent, was to prevent the presentation
of mitigating evidence at his sentencing.’’); Johnson v.
State, supra, 117 Nev. 161 (‘‘the record reflects that
[the defendant] asserted his right to self-representation
mainly because of the ‘conflict of interests’ arising out
of his differences with his counsel over the insanity
defense’’).
   We also flatly reject the petitioner’s contention that,
even if defense counsel could not advance an extreme
emotional disturbance argument, they still could (and
should) have presented evidence supporting that the-
ory. The only substantive evidence supporting such a
theory would have been elicited, perforce, from the
petitioner himself, who plainly was not willing to sup-
port such an effort, or from one of the defense mental
health professionals, whose testimony the petitioner
advised the court he did not want. We fail to see how
such an approach would be faithful to the petitioner’s
emphatic instructions. The fact that an extreme emo-
tional disturbance instruction may be given despite a
defendant’s refusal to pursue such a defense is not to
the contrary. See, e.g., State v. Asherman, 193 Conn.
695, 729–31, 478 A.2d 227 (1984), cert. denied, 470 U.S.
1050, 105 S. Ct. 1749, 84 L. Ed. 2d 814 (1985). This
instruction inures at least equally to the state’s benefit
so as not to require a jury to acquit a defendant if a
reasonable doubt arises as to intent or some other ele-
ment of the offense. See id., 731–32. Accordingly,
defense counsel’s reluctant acquiescence to the peti-
tioner’s insistence on proceeding exclusively under a
defense of reasonable doubt did not constitute ineffec-
tive assistance of counsel.
                            B
       Ineffective Assistance of Counsel in the
                Petition for a New Trial
   The petitioner claims the habeas court improperly
concluded that he had no statutory or constitutional
right to counsel in his petition for a new trial and thus
no corresponding right to effective assistance. He con-
tends that every federal circuit to address this issue
has concluded that a posttrial, preappeal motion for a
new trial is a critical stage of the criminal proceedings,
to which the constitutional right to counsel attaches,
and that his petition for a new trial is subject to this
same treatment. We disagree.
  A predicate to the right to effective assistance of
counsel is the right to counsel. See McMann v. Richard-
son, 397 U.S. 759, 771 n.14, 90 S. Ct. 1441, 25 L. Ed. 2d
763 (1970) (‘‘[i]t has long been recognized that the right
to counsel is the right to the effective assistance of
counsel’’). ‘‘The [s]ixth [a]mendment safeguards to an
accused who faces incarceration the right to counsel
at all critical stages of the criminal process.’’ Iowa v.
Tovar, supra, 541 U.S. 80–81. As the respondent prop-
erly points out, there are substantive differences
between a motion for a new trial and a petition for a
new trial under Connecticut law that explain why the
former is a critical stage of the criminal process and
the latter is not.
   A motion for a new trial is filed ‘‘within the technical
confines of the docketed criminal case. No separate
civil action [i]s brought. . . . [A] petition [for a new
trial] is instituted by a writ and complaint served on
the adverse party; although such an action is collateral
to the action in which a new trial is sought, it is by
its nature a distinct proceeding. The judgment on the
petition terminates the suit which renders it final. On
the contrary, a motion for a new trial is filed in a case
then in progress or pending and is merely a gradation
in that case leading to a final judgment. . . . [E]rrors
which are claimed to have been committed in rendering
the judgment on a petition for a new trial are not review-
able on an appeal from the judgment rendered in the
action in which a new trial is sought. . . . On the other
hand, errors which are claimed in relation to a motion
for a new trial may be assigned on the appeal from the
judgment rendered in the case in which the motion is
made.’’ (Citations omitted; emphasis added; footnote
omitted.) State v. Asherman, 180 Conn. 141, 143–44,
429 A.2d 810 (1980); accord State v. Goodwin, 3 Conn.
Cir. Ct. 386, 388, 215 A.2d 913, cert. denied, 153 Conn.
725, 213 A.2d 525 (1965).
   For the preceding reasons, a motion for a new trial
is a critical stage of the criminal proceedings, to which
the right to counsel attaches, whereas a petition for a
new trial is a distinct proceeding. The latter is related
to and can affect the criminal judgment in the same
way that a habeas proceeding may. There is no constitu-
tional right to habeas counsel, however, only a statutory
right. See Gipson v. Commissioner of Correction, 257
Conn. 632, 646 nn.19 and 20, 778 A.2d 121 (2001). The
statutory right to counsel has not been extended to
petitions for a new trial. See General Statutes § 51-296
(a). Therefore, the habeas court properly determined
that the petitioner could not advance a claim of ineffec-
tive assistance of counsel in his petition for a new trial.
                            C
                     Cumulative Error
   The petitioner contends that the habeas court
improperly concluded that his claims that the cumula-
tive prejudicial effect of counsel’s deficient perfor-
mance either constituted ineffective assistance or a
violation of due process were not cognizable under
Connecticut law. He contends that cumulative error is
a valid basis on which to grant relief under federal and
Connecticut case law.
   It appears to be an open question whether such claims
are cognizable under Connecticut law. Compare Hinds
v. Commissioner of Correction, 321 Conn. 56, 95, 136
A.3d 596 (2016) (‘‘even if we were to recognize the [due
process] cumulative error doctrine as articulated in the
federal courts and to deem it applicable to habeas pro-
ceedings, the trial improprieties in the present case
would not justify relief under that doctrine’’), with State
v. Harris, 182 Conn. 220, 232, 438 A.2d 38 (1980) (‘‘The
final portion of the cumulative error argument concerns
the ineffectiveness of the defendant’s trial counsel.
Because this claim has an independent basis in the sixth
amendment to the United States constitution, we review
the defendant’s contentions in this respect both as com-
bining with the first two categories of cumulative error
resulting in the denial of a fair trial and on its own
merits with respect to the defendant’s independent right
to the effective assistance of counsel.’’). Nonetheless,
we need not resolve this question in the present case.
We have previously concluded that any purported defi-
ciencies caused no prejudice to the petitioner in light
of his refusal to aid in presenting mitigation evidence
and his resolute instructions to his attorneys not to
present any such evidence. In other words, there is no
prejudice to aggregate.
                             D
             Brady Violation for Failing to
               Disclose 1966 Transcripts
   Finally, the petitioner contends that the habeas court
improperly concluded that the state did not suppress
the 1966 transcripts in violation of Brady because
defense counsel’s discovery requests did not seek these
documents and the state’s open file policy was sufficient
to discharge its Brady obligations. In light of our conclu-
sions in part III A 1 of this opinion, the petitioner cannot
prevail even if this contention is correct.
  ‘‘In order to prove a Brady violation, the defendant
must show: (1) that the prosecution suppressed evi-
dence after a request by the defense; (2) that the evi-
dence was favorable to the defense; and (3) that the
evidence was material.’’ (Internal quotation marks omit-
ted.) State v. Smith, 313 Conn. 325, 348, 96 A.3d 1238
(2014). ‘‘[T]he test for materiality under Brady and the
test for prejudice under Strickland [for ineffective assis-
tance of counsel] are the same . . . .’’ Lapointe v. Com-
missioner of Correction, 316 Conn. 225, 266–67, 112
A.3d 1 (2015). Because we have already concluded that
the petitioner failed to establish prejudice under Strick-
land in relation to these transcripts, he cannot establish
that they are material under Brady.
                             E
                       Conclusion
   The habeas court properly concluded that the peti-
tioner had not established a basis for relief on any of
his claims challenging his judgment of conviction. In
light of intervening changes in the law, the petitioner’s
claims challenging the penalty phase and resulting sen-
tence of death have been rendered moot. The petitioner
is free to file a motion to correct an illegal sentence
pursuant to Practice Book § 43-22.
   The appeal is dismissed with respect to the petition-
er’s claims regarding the imposition of a sentence of
death; the judgment is affirmed.
   In this opinion the other justices concurred.
   * This case was originally argued before a panel of this court consisting
of Chief Justice Rogers and Justices Palmer, Zarella, Eveleigh, McDonald
and Robinson. Thereafter, Justice Zarella retired from this court and did
not participate in the consideration of the case.
   1
     The trial court, Heiman, J., rendered judgment with respect to the capital
felony count only and not the lesser included murder counts in light of
the double jeopardy clause of the fifth amendment to the United States
constitution. See State v. Breton, 264 Conn. 327, 333, 824 A.2d 778, cert.
denied, 540 U.S. 1055, 124 S. Ct. 819, 157 L. Ed. 2d 708 (2003); State v.
Breton, 235 Conn. 206, 215 n.8, 663 A.2d 1026 (1995).
   2
     General Statutes (Rev. to 1987) § 53a-54a provides in relevant part: ‘‘(a)
A person is guilty of murder when, with intent to cause the death of another
person, he causes the death of such person . . . except that in any prosecu-
tion under this subsection, it shall be an affirmative defense that the defen-
dant committed the proscribed act or acts under the influence of extreme
emotional disturbance for which there was a reasonable explanation or
excuse, the reasonableness of which is to be determined from the viewpoint
of a person in the defendant’s situation under the circumstances as the
defendant believed them to be, provided nothing contained in this subsection
shall constitute a defense to a prosecution for, or preclude a conviction of,
manslaughter in the first degree or any other crime.
   ‘‘(b) Evidence that the defendant suffered from a mental disease, mental
defect or other mental abnormality is admissible, in a prosecution under
subsection (a), on the question of whether the defendant acted with intent
to cause the death of another person. . . .’’
   3
     The petitioner’s account was remarkably similar to the narrative that
the state had presented to the jury at the guilt phase, which it had constructed
on the basis of physical evidence at the scene. See Breton II, supra, 235
Conn. 212–14.
   4
     In Breton III, this court interpreted a statement Borden made to mean
that the petitioner had said that he thought he had seen someone walking
around ‘‘inside.’’ Breton III, supra, 264 Conn. 346. No one expressly referred
to inside, however, and it is clear from the totality of the evidence that
the petitioner indicated that he thought he had seen someone outside the
apartment. Borden initially testified that the petitioner had stated that while
he was sitting in his truck, he thought he saw ‘‘someone walking around
the house,’’ and later clarified that the petitioner had said that he had seen
someone walking around outside. The latter is consistent with a contempora-
neous report of the petitioner’s narrative to Borden, as well as the petitioner’s
account of the events after he entered the apartment, which do not reflect
any concern that a stranger might be present inside. In fact, a witness
testified at the guilt phase that he was outside at the apartment complex
at approximately 4:30 a.m. when he observed the petitioner leaving the
apartment and thought that the petitioner had looked right at him.
   5
     The state suggested that this comment reflected the petitioner’s anger
that neither his son nor his former wife had sent a card for the petitioner’s
birthday, which was December 10, three days earlier.
   6
     The record does not make clear why the petition was withdrawn with
prejudice.
   7
     The long gap between the criminal trial and the habeas trial stems from
several factors. As a result of the petitioner’s three appeals to this court,
and a petition for certification to appeal to the United States Supreme Court,
the judgment in the petitioner’s criminal trial was not final until 2003. Then,
several years lapsed due to a shared assumption by the parties that this
habeas case would not go forward until the resolution of another habeas
proceeding concluded in which the petitioner’s claim of unconstitutional
racial disparities in the administration of the death penalty was consolidated
with those of other petitioners raising that claim. Eventually, the present
habeas action proceeded, after it became evident that the consolidated
habeas action was not going to conclude in the near term. The latter was
concluded in 2013. See In re Death Penalty Disparity Claims, Superior
Court, judicial district of Tolland, Docket No. CV-05-4000632-S (October
11, 2013).
   8
     ‘‘While intoxication is neither a defense nor an affirmative defense to a
murder charge in Connecticut, evidence of a defendant’s intoxication is
relevant to negate specific intent which is an essential element of the crime
of murder.’’ State v. Stevenson, 198 Conn. 560, 568, 504 A.2d 1029 (1986);
see General Statutes § 53a-7 (‘‘[i]ntoxication shall not be a defense to a
criminal charge, but in any prosecution for an offense evidence of intoxica-
tion of the defendant may be offered by the defendant whenever it is relevant
to negate an element of the crime charged’’).
   9
     Mark Rademacher filed the petition in 1999, but Norman Pattis and
James Nugent assumed representation of the petitioner in 2002. Pattis and
Nugent were claimed to have been ineffective.
   10
      The majority also concluded that the mitigating evidence at issue would
not have changed the result. See Schriro v. Landrigan, supra, 550 U.S. 481.
   11
      In cases in which there was only a challenge to counsel’s failure to
present mitigating evidence, not to counsel’s failure to investigate such
evidence, several state courts have required, as a matter of state law, that
a waiver of the right to present mitigating evidence must be knowing, volun-
tary, and intelligent. See State v. Hausner, 230 Ariz. 60, 84–86, 280 P.3d 604
(2012) (en banc); Koon v. Dugger, 619 So. 2d 246, 248–50 (Fla. 1993); St.
Clair v. Commonwealth, 140 S.W.3d 510, 560–61 (Ky. 2004); State v. Short,
129 Ohio St. 3d 360, 368–69, 952 N.E.2d 1121 (2011); State v. Johnson, 401
S.W.3d 1, 13 (Tenn.), cert. denied,          U.S.      , 134 S. Ct. 513, 187 L.
Ed. 2d 371 (2013). At least one state court has treated this standard as
constitutionally mandated, albeit prior to Schriro. See State v. Woods, 143
Wn. 2d 561, 609, 23 P.3d 1046 (‘‘[l]ike other constitutional rights, a defendant
may waive the right to present mitigating evidence so long as the waiver is
made ‘knowingly, voluntarily, and intelligently’ ’’), cert. denied, 534 U.S. 964,
122 S. Ct. 374, 151 L. Ed. 2d 285 (2001). Most of these state courts require
a colloquy to ensure that this standard has been met. There is a split among
these courts as to whether it is proper to inquire into the nature of the
mitigating evidence that counsel had discussed with the defendant.
   12
      The Ninth Circuit appears to be alone in concluding that Schriro ‘‘is
inapplicable where the defendant did not threaten to obstruct the presenta-
tion of any mitigating evidence that counsel found,’’ and therefore does not
apply when a defendant directs counsel not to present mitigation evidence.
(Internal quotation marks omitted.) Stankewitz v. Wong, 698 F.3d 1163, 1170
n.2 (9th Cir. 2012); see, e.g., Newland v. Hall, 527 F.3d 1162, 1205 (11th Cir.
2008) (‘‘[w]hile [the] petitioner’s conduct in this case is not as extreme as
the defendant’s conduct in Schriro, we follow the [c]ourt in drawing a
distinction between a defendant’s passive [noncooperation] and his active
instruction to counsel not to engage in certain conduct’’), cert. denied, 555
U.S. 1183, 129 S. Ct. 1336, 173 L. Ed. 2d 607 (2009).
   13
      We agree with the petitioner that his refusal to admit to committing the
crimes would not preclude the presentation of such a defense solely through
expert testimony. We also agree with the petitioner that the risk that he
might insist on testifying to disavow having committed the crimes would
not preclude successfully establishing that defense. In fact, in Borden’s
testimony at the first penalty phase hearing to establish mitigation, defense
counsel elicited testimony on that very issue. Borden testified that, after
their first meeting, the petitioner disavowed having committed the crimes
and, when confronted with his earlier confession, the petitioner claimed
that it was just ‘‘a story.’’ Borden discussed this retraction in a manner to
bolster his diagnosis of severe mixed personality disorder.
   14
      North Carolina v. Alford, 400 U.S. 25, 37, 91 S. Ct. 160, 27 L. Ed. 2d
162 (1970).
   15
      As the Eleventh Circuit explained: ‘‘[A] mentally competent, intelligent
defendant, having been convicted of a brutal murder, faced life imprisonment
or death. Insisting on doing things his way, he chose death and prevented
his counsel from attempting to secure a life sentence through the develop-
ment and presentation of mitigating circumstances evidence. That is not a
choice that most people would have made, but it is one that he had the
right to make, and he made it voluntarily and with full awareness of the
consequences. . . . What [the defendant] does not have is the right to
escape the consequences of his own decision not to present any mitigating
circumstances evidence by shifting the blame for it to someone else.’’ (Cita-
tion omitted.) Allen v. Secretary, Florida Dept. of Corrections, supra, 611
F.3d 765.
   16
      We also note that when Phillips reviewed the 1966 transcripts in 2002,
she thought that they were significant, but did not contradict previous
findings. Rather, they provided stronger evidence in support of a conclusion
that the petitioner was experiencing a dissociative episode when he killed
his former wife and his son. Like Borden, she believed that further testing
would be required to make additional diagnoses. The petitioner, however,
would not meet with the criminal trial experts after December, 1988. No
effort was made to have Phillips or Borden undertake such testing for
the habeas trial. Rather, the petitioner’s habeas experts largely relied on
information previously provided by the petitioner to Borden in February,
1988, and supplemented that information with tests they administered to
the petitioner more than twenty years after the criminal trial.
   17
      Blumberg drew a material distinction between PTSD and mixed person-
ality disorder with respect to whether those conditions would be affected
by methamphetamine intoxication. He opined that methamphetamine intoxi-
cation would exacerbate PTSD but not mixed personality disorder.
   18
      Although we base our decision on Strickland’s prejudice prong, we note
that our review of the record yielded evidence that calls into question
whether the petitioner proved that counsel’s performance was deficient.
The habeas court could not envision a tactical reason not to test the sample,
but that conclusion necessarily presupposed that counsel knew or should
have known about the effects of Desoxyn on a person with the petitioner’s
mental condition when investigating the case prior to the 1989 guilt phase.
Differences in Borden’s testimony at the two penalty phase hearings, how-
ever, suggest that Desoxyn’s dangers, in general or in specific to someone
with the petitioner’s mental disorders, were not generally known to the
medical community in 1989. When Borden testified at the first penalty phase
in 1989, he offered limited, innocuous testimony about Desoxyn, simply
describing it as ‘‘a diet pill which gives you a high. [It] was one of the first
antidepressants.’’ When Borden testified at the second penalty phase in
1997, he characterized the drug’s effects as far more dangerous—a metham-
phetamine with a potent stimulant effect, ten times more powerful than
cocaine, the worst medication that could have been prescribed for someone
with the petitioner’s mental illness, a drug that could trigger violent behavior,
and a drug that when used in combination with alcohol would be like
‘‘throwing gasoline’’ on a ‘‘simmering fire.’’ When questioned about the differ-
ences between his testimony, first by the state and then on redirect by the
defense, Borden explained that the medical community’s knowledge about
the deleterious effects of the drug had greatly evolved since 1989, so much
so that the drug was no longer prescribed. An evolved state of knowledge
would explain why the defense’s list of mitigating factors expressly included
intoxication in the second penalty phase and not in the first penalty phase.
In assessing whether the defense’s investigation was deficient, Strickland
requires us to focus on counsel’s perspective at the time investigative deci-
sions were made. See Rompilla v. Beard, supra, 545 U.S. 381.
   We note that if neither Borden nor defense counsel knew about Desoxyn’s
potential dangers, defense counsel’s discussions regarding the use of intoxi-
cation evidence could have been directed at the petitioner’s use of other
prescription medications as well as alcohol consumption. Borden also testi-
fied at the second penalty phase that the effects of Fiorinal, a barbiturate,
are dangerous for a disturbed person and its effects are amplified when
mixed with alcohol. Nonetheless, because both parties implicitly assume
that Borden, and, in turn, the defense, knew about Desoxyn’s dangers, our
analysis similarly proceeds from such an assumption.
   19
      The petitioner’s sister testified at the second penalty phase that the
thirty day supply was ‘‘almost all gone’’ when she found it. She was never
asked to quantify that remark.
   20
      The petitioner’s reliance on Lapointe v. Commissioner of Correction,
316 Conn. 225, 293–94, 112 A.3d 1 (2015), for the proposition that he met
his burden of proof because a jury reasonably could have credited his
experts’ opinions and find a reasonable doubt as to his specific intent due
to intoxication is misplaced. In Lapointe, we declined to defer to the habeas
court’s finding that the opinions of the petitioner’s experts were not persua-
sive because the habeas court’s criticism of those experts’ opinions was
not premised on a credibility assessment, but instead on facts that were
manifestly contradicted by the record. Id., 276–89. In light of the lack of
support for the habeas court’s finding, we scoured the record to determine
whether it revealed any other apparent reason why a jury would be apt to
discredit the testimony of the petitioner’s experts. Id., 290. In the present
case, the habeas court reasonably found that the petitioner’s experts had
failed to establish a credible and adequate foundation for their intoxica-
tion opinion.
