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      CARMINE KELLMAN v. COMMISSIONER OF
                 CORRECTION
                  (AC 39429)
                      Sheldon, Elgo and Mihalakos, Js.

                                    Syllabus

The petitioner, who previously had been convicted of, inter alia, murder in
    connection with the shooting death of the victim, sought a writ of
    habeas corpus, claiming that his trial counsel, S, had provided ineffective
    assistance. The habeas court rendered judgment denying the habeas
    petition, concluding that the petitioner had failed to prove that he was
    denied the effective assistance of trial counsel. Thereafter, on the grant-
    ing of certification, the petitioner appealed to this court. Held:
1. The petitioner could not prevail on his claim that S provided ineffective
    assistance by failing to meaningfully present and explain a pretrial plea
    offer from the state; the habeas court’s finding that the petitioner failed to
    demonstrate that he was prejudiced by his counsel’s allegedly deficient
    performance during pretrial plea negotiations was not clearly erroneous,
    as the habeas court did not find credible the petitioner’s testimony
    regarding whether a plea deal was presented or meaningfully explained
    to him, and the petitioner failed to establish that it was reasonably
    probable that he would have accepted the plea offer.
2. The habeas court did not err in determining that the petitioner failed to
    establish his claim that S was ineffective by employing a deficient trial
    strategy that pursued an extreme emotional disturbance defense at trial,
    without consulting with an expert on that defense prior to trial: that
    court’s finding that S’s decision not to retain an expert witness in pursu-
    ing the extreme emotional disturbance defense was a reasonable strate-
    gic decision was not clearly erroneous and was supported by the
    evidence and testimony at the habeas trial, including S’s testimony that
    he believed that it was not prudent to call an expert witness on that
    defense when the petitioner and lay witnesses could testify to the same
    evidence, that he was concerned that the jury would have looked unfa-
    vorably on an expert who was paid to testify on the petitioner’s behalf,
    and that it was the only defense he had given the strength of the evidence
    against the petitioner; moreover, even if S was deficient in his perfor-
    mance by failing to consult with an expert on the extreme emotional
    disturbance defense, the petitioner did not show that S’s allegedly defi-
    cient performance prejudiced him, as there was substantial evidence in
    the record that supported the jury’s guilty verdict, and, although the
    petitioner speculated that the result might have been different had S
    chosen to utilize an expert witness, the petitioner failed to demonstrate
    that there was a reasonable probability that if S had consulted with or
    called an expert witness during the criminal trial, the jury would have
    had reasonable doubt as to the petitioner’s guilt.
       Argued September 14—officially released November 14, 2017

                              Procedural History

  Amended petition for a writ of habeas corpus,
brought to the Superior Court in the judicial district of
Tolland, and tried to the court, Oliver, J.; judgment
denying the petition, from which the petitioner, on the
granting of certification, appealed to this court.
Affirmed.
   Stephen A. Lebedevitch, for the appellant (petitioner).
   Lisa A. Riggione, senior assistant state’s attorney,
with whom, on the brief, were Patrick J. Griffin, state’s
attorney, and Adrienne Russo, deputy assistant state’s
attorney, for the appellee (respondent).
                          Opinion

   MIHALAKOS, J. The petitioner, Carmine Kellman,
also known as Carmi Kellman,1 appeals following the
habeas court’s granting of his petition for certification
to appeal from its judgment denying his petition for a
writ of habeas corpus. On appeal, the petitioner claims
that the habeas court improperly rejected his claims of
ineffective assistance of trial counsel. Specifically, he
asserts that his trial counsel, Richard Silverstein, ren-
dered ineffective assistance because he (1) failed to
meaningfully present and explain the state’s pretrial
plea offers and (2) failed to consult with or present an
expert at the petitioner’s trial regarding the extreme
emotional disturbance defense. For the reasons set
forth herein, we affirm the judgment of the habeas
court.
   The following facts and procedural history are rele-
vant to our disposition of the petitioner’s claims. After
a jury trial, the petitioner was convicted of murder in
the first degree in violation of General Statutes § 53a-
54a, carrying a pistol without a permit in violation of
General Statutes § 29-35, and criminal violation of a
protective order in violation of General Statutes (Rev.
to 1993) § 53a-110b (a) (now § 53a-223).2 The petitioner
was sentenced to sixty years of incarceration for mur-
der, one year concurrent for carrying a pistol without
a permit, and one year concurrent for criminal violation
of a protective order.
   The petitioner’s conviction was the subject of a direct
appeal before this court. See State v. Kellman, 56 Conn.
App. 279, 742 A.2d 423, cert. denied, 252 Conn. 939, 747
A.2d 4 (2000). In affirming the petitioner’s conviction,
this court concluded that the jury reasonably could
have found the following facts. The petitioner and the
victim, Carmen Smith, began a two year romantic rela-
tionship in 1992, which was marked by repeated domes-
tic incidents, breakups, and reconciliations. Id., 280.
Numerous complaints were lodged with the police by
the victim about the petitioner. Id. In July, 1993, after
an arrest based on such a complaint, the petitioner was
ordered by the victim to move out of her residence. Id.
The petitioner returned during a brief period of reconcil-
iation, but was dispossessed permanently by the victim
later that year. Id., 280–81.
   As the petitioner continued to pursue the relation-
ship, his behavior became more hostile, and the domes-
tic incidents increased in severity. Id., 281. In February,
1994, the petitioner was arrested outside the victim’s
residence after being pursued by the police. Id. There-
after, the victim obtained a protective order that prohib-
ited the petitioner from entering her home and from
restraining, harassing or contacting her. Id. The peti-
tioner, however, continued to harass the victim on many
occasions. Id. On Saturday, March 12, 1994, the victim
and her sister went shopping, had dinner and went to
a club for the evening. Id. At approximately 2 a.m., on
March 13, 1994, they returned to the victim’s house,
where the petitioner was waiting in the driveway. Id.
As the petitioner approached the two women, he pulled
out a gun, chased the victim down a walkway alongside
the building, and shot her five times, causing her
death. Id.
  The following day, the petitioner admitted to a friend
that he had been involved in the shooting that led to
the victim’s death. Id., 282. After his arrest, he claimed
that the shooting was an unintended mistake. Id. At
his criminal trial, the petitioner claimed that he was
suffering from extreme emotional disturbance and that
he was intoxicated when he shot the victim. Id.
   Following his conviction, the petitioner, on May 15,
2013, filed a pro se petition for a writ of habeas corpus,
alleging that his trial attorney, Silverstein, provided inef-
fective assistance of counsel. Specifically, the petitioner
alleged that Silverstein advised him to reject a thirty
year plea agreement because he could win the case at
trial. On the basis of this advice, he rejected the state’s
offer, went to trial, and was convicted. On June 18,
2015, the petitioner, represented by appointed counsel,
filed an amended petition, in which he alleged that
he was denied his constitutional right to the effective
assistance of counsel as a result of Silverstein’s (1)
deficient performance in plea negotiations and (2) fail-
ure to consult with an expert on the extreme emotional
disturbance defense.3 The petitioner first claimed that:
‘‘(a) [Silverstein] failed to inform the petitioner that the
state made a pretrial offer in an attempt to resolve
the case; (b) [Silverstein] failed to meaningfully and
adequately advise the petitioner with respect to the
state’s pretrial offer; (c) [Silverstein] rejected the state’s
pretrial offer without the authorization or consent of
the petitioner; and/or (d) assuming [Silverstein] did
relay the offer to the petitioner, he advised the peti-
tioner to reject the offer and proceed to trial.’’ The
petitioner claimed that but for his counsel’s deficient
performance relating to the plea offers, ‘‘there is a rea-
sonable probability that . . . the results of the pro-
ceedings would have been more favorable to [him] in
that [he] would have accepted the state’s offer, and the
trial court would have imposed the sentence pursuant
to the offer.’’ Second, the petitioner claimed that Sil-
verstein pursued an unreasonable legal strategy in pre-
senting the extreme emotional disturbance affirmative
defense, more particularly, by ‘‘fail[ing] to obtain the
opinion of an expert or get the [petitioner] evaluated
by an expert,’’ and that this ‘‘unreasonable legal strategy
prejudiced the petitioner.’’
   The habeas trial was held on November 18, 2015, and
March 2, 2016. The petitioner presented testimony from
Silverstein, the prosecutor in the petitioner’s criminal
trial, Attorney James Dinnan, and the petitioner’s expert
in criminal defense, Attorney J. Patten Brown. The peti-
tioner also testified. On June 21, 2016, the habeas court,
Oliver, J., issued a written memorandum of decision
denying the petition for a writ of habeas corpus, finding
that the petitioner had failed to prove that he was denied
the effective assistance of trial counsel under the two-
pronged test set forth in Strickland v. Washington, 466
U.S. 668, 104 S. Ct. 2052, 80 L. Ed. 2d 674 (1984). The
habeas court granted the petition for certification to
appeal. This appeal followed. Additional facts and pro-
cedural history will be introduced as necessary.
   We first set forth the standard of review and legal
principles applicable to the petitioner’s appeal. ‘‘Our
standard of review of a habeas court’s judgment on
ineffective assistance of counsel claims is well settled.
The habeas court is afforded broad discretion in making
its factual findings, and those findings will not be dis-
turbed 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. . . . Therefore, our review of whether the facts
as found by the habeas court constituted a violation of
the petitioner’s constitutional right to effective assis-
tance of counsel is plenary.’’ (Citation omitted; internal
quotation marks omitted.) Sanders v. Commissioner
of Correction, 169 Conn. App. 813, 822, 153 A.3d 8
(2016), cert. denied, 325 Conn. 904, 156 A.3d 536 (2017).
   It is well established that ‘‘[a] criminal defendant is
constitutionally entitled to adequate and effective assis-
tance of counsel at all critical stages of criminal pro-
ceedings . . . . This right arises under the sixth and
fourteenth amendments to the United States constitu-
tion and article first, § 8, of the Connecticut constitu-
tion. . . . It is axiomatic that the right to counsel is the
right to the effective assistance of counsel.’’ (Internal
quotation marks omitted.) Horn v. Commissioner of
Correction, 321 Conn. 767, 775, 138 A.3d 908 (2016).
   ‘‘A claim of ineffective assistance of counsel as enun-
ciated in Strickland v. Washington, supra, 466 U.S. 668,
consists of two components: a performance prong and
a prejudice prong. To satisfy the performance prong
. . . the petitioner must demonstrate that his attorney’s
representation was not reasonably competent or within
the range of competence displayed by lawyers with
ordinary training and skill in the criminal law.’’ (Internal
quotation marks omitted.) Griffin v. Commissioner of
Correction, 137 Conn. App. 382, 387, 47 A.3d 956, cert.
denied, 307 Conn. 921, 54 A.3d 182 (2012). ‘‘Our
Supreme Court has stated that the performance inquiry
must be whether counsel’s assistance was reasonable
considering all the circumstances, and that [j]udicial
scrutiny of counsel’s performance must be highly defer-
ential.’’ (Internal quotation marks omitted.) Id., quoting
Ham v. Commissioner of Correction, 301 Conn. 697,
706, 23 A.3d 682 (2011).
   ‘‘An error by counsel, even if professionally unreason-
able, does not warrant setting aside the judgment of a
criminal proceeding if the error had no effect on the
judgment. . . . To satisfy the second prong of Strick-
land, that his counsel’s deficient performance preju-
diced his defense, the petitioner must establish that, as
a result of his trial counsel’s deficient performance,
there remains a probability sufficient to undermine con-
fidence in the verdict that resulted in his appeal. . . .
The second prong is thus satisfied if the petitioner can
demonstrate that there is a reasonable probability that,
but for that ineffectiveness, the outcome would have
been different.’’ (Internal quotation marks omitted.)
Horn v. Commissioner of Correction, supra, 321 Conn.
776. ‘‘In making this determination, a court hearing an
ineffectiveness claim [based on counsel’s failure to
investigate] must consider the totality of the evidence
before the judge or the jury. . . . Some errors will have
had a pervasive effect on the inferences to be drawn
from the evidence, altering the entire evidentiary pic-
ture, and some will have had an isolated, trivial effect.
Moreover, a verdict or conclusion only weakly sup-
ported by the record is more likely to have been affected
by errors than one with overwhelming record support.’’
(Internal quotation marks omitted.) Id., quoting Strick-
land v. Washington, supra, 466 U.S. 695–96.
   A petitioner’s claim will ‘‘succeed only if both prongs
are satisfied. . . . Unless a [petitioner] makes both
showings, it cannot be said that the conviction . . .
resulted from a breakdown in the adversary process
that renders the result unworkable.’’ (Citation omitted;
internal quotation marks omitted.) Boyd v. Commis-
sioner of Correction, 130 Conn. App. 291, 295, 21 A.3d
969, cert. denied, 302 Conn. 926, 28 A.3d 337 (2011). ‘‘A
court can find against a petitioner, with respect to a
claim of ineffective assistance of counsel, on either the
performance prong or the prejudice prong, whichever
is easier.’’ Ham v. Commissioner of Correction, supra,
301 Conn. 704.
                             I
   The petitioner first claims that Silverstein provided
ineffective assistance either by failing to inform him
that the state had made a pretrial plea offer, or, alterna-
tively, if he was informed of the offer, that Silverstein
did not meaningfully explain the plea offer to him.
   The United States Supreme Court has held that pre-
trial negotiations implicating the decision as to whether
to plead guilty is a critical stage in criminal proceedings
for purposes of the sixth amendment right to effective
assistance of counsel. ‘‘To show prejudice from ineffec-
tive assistance of counsel where a plea offer has lapsed
or been rejected because of counsel’s deficient perfor-
mance, defendants must demonstrate a reasonable
probability they would have accepted the earlier plea
offer had they been afforded effective assistance of
counsel. Defendants must also demonstrate a reason-
able probability the plea would have been entered with-
out the prosecution canceling it or the trial court
refusing to accept it, if they had the authority to exercise
that discretion under state law. To establish prejudice
in this instance, it is necessary to show a reasonable
probability that the end result of the criminal process
would have been more favorable by reason of a plea
to a lesser charge or a sentence of less prison time.’’
Missouri v. Frye, 566 U.S. 134, 147, 132 S. Ct. 1399, 182
L. Ed. 2d 379 (2012); see also Padilla v. Kentucky, 559
U.S. 356, 364, 130 S. Ct. 1473, 176 L. Ed. 2d 284 (2010)
(‘‘[b]efore deciding whether to plead guilty, a defendant
is entitled to the effective assistance of competent coun-
sel’’ [internal quotation marks omitted]).
   The petitioner claims that Silverstein’s performance
during the pretrial plea negotiations fell below objec-
tively reasonable standards. On this issue, the habeas
court determined only that the petitioner had not met
his burden on the prejudice prong. We need not address
the performance prong of Strickland v. Washington,
supra, 466 U.S. 687, on appeal because the habeas court
did not address the performance of the petitioner’s
counsel as it relates to pretrial plea negotiations, nor
was the habeas court required to do so. ‘‘[A] court
need not determine whether counsel’s performance was
deficient before examining the prejudice suffered by
the defendant as a result of the alleged deficiencies.
. . . If it is easier to dispose of an ineffectiveness claim
on the ground of lack of sufficient prejudice . . . that
course should be followed.’’ (Internal quotation marks
omitted.) State v. Brown, 279 Conn. 493, 525–26, 903
A.2d 169 (2006); see also Elsey v. Commissioner of
Correction, 126 Conn. App. 144, 162, 10 A.3d 578, cert.
denied, 300 Conn. 922, 14 A.3d 1007 (2011) (‘‘[b]ecause
both prongs . . . [of the Strickland test] must be estab-
lished for a habeas petitioner to prevail, a court may
dismiss a petitioner’s claim if he fails to meet either
prong’’ [internal quotation marks omitted]).
    The petitioner’s claim concerning whether a plea deal
was presented or meaningfully explained to him, specif-
ically, whether this prejudiced him, depends entirely
on the habeas court’s determinations on credibility, to
which we defer on appeal. ‘‘The habeas judge, as the
trier of the facts, is the sole arbiter of the credibility of
witnesses and the weight to be given to their testimony.’’
(Internal quotation marks omitted.) Vidro v. Commis-
sioner of Correction, 105 Conn. App. 362, 366, 938 A.2d
607, cert. denied, 286 Conn. 908, 944 A.2d 982 (2008).
‘‘It is well established that a reviewing court is not in
the position to make credibility determinations. . . .
This court does not retry the case or evaluate the credi-
bility of the witnesses. . . . Rather, we must defer to
the [trier of fact’s] assessment of the credibility of the
witnesses based on its firsthand observation of their
conduct, demeanor and attitude.’’ (Internal quotation
marks omitted.) Lewis v. Commissioner of Correction,
117 Conn. App. 120, 125–26, 977 A.2d 772, cert. denied,
294 Conn. 904, 982 A.2d 647 (2009). Because the peti-
tioner’s claim is premised entirely on issues of credibil-
ity, he cannot prevail.
   In the present case, the habeas court summarily dis-
missed the petitioner’s testimony as ‘‘loose, equivocal
and unconvincing,’’ based on his equivocations regard-
ing whether he was made aware of the plea offer, both
in his conflicting habeas petitions and his testimony at
the habeas trial. The following exchange between the
petitioner and the court highlights the inconsistencies
between the two petitions for writ of habeas corpus:
   ‘‘[The Court]: . . . Were you ever aware of an offer
from the prosecutor?
  ‘‘[The Petitioner]: Never aware of the offer.
  ‘‘[The Court]: I’m sorry?
  ‘‘[The Petitioner]: Never aware of the offer, no. . . .
  ‘‘[The Court]: Did anyone ever tell you that there was
an offer from a prosecutor short of going to trial and
being convicted?
  ‘‘[The Petitioner]: Well, like I mentioned, the prosecu-
tor, Silverstein, mentioned it was an offer, but he never
told me what the offer was. . . .
  ‘‘[The Court]: Okay. Did Attorney Silverstein ever tell
you—so is it fair to say that you never heard a number
until you heard the number thirty from someone?
  ‘‘[The Petitioner]: Yeah, I never heard a number.
  ‘‘[The Court]: And you never heard a number from
Attorney Silverstein, ever?
  ‘‘[The Petitioner]: Never.
  ‘‘[The Court]: Where did you get the number you
wrote in your self-represented petition? Let’s see here.
You wrote . . . ‘I claim Attorney Silverstein advised
me to reject a thirty year plea agreement and he advised
me that he can win my case at trial.’ What do you mean
when you wrote that? It seems pretty clear to me, but
what did you mean when you wrote that?
  ‘‘[The Petitioner]: I wrote it because, after I found
out that the thirty, thirty-five years was the . . . you
know, was the offer, which I learned from another attor-
ney before . . . before [Attorney Ashley] Hopkins.
   ‘‘[The Court]: Okay. And you said something just now
that’s not what you wrote. You said thirty to thirty-
five. Who told you—well, why did you write, ‘I claim
Attorney Silverstein advised me to reject a thirty year
plea agreement.’ Why did you write that?
  ‘‘[The Petitioner]: [Attorney] Carpenter told me about
the plea offer . . . so that’s how I found out, through
[Attorney Jerry Rosenblum’s] records.4
  ‘‘[The Court]: Found out what?
  ‘‘[The Petitioner]: That there was . . . an offer.
[There] was an offer on the table.
  ‘‘[The Court]: Offer of what?
  ‘‘[The Petitioner]: Of thirty-five or thirty and the
forty. . . .
  ‘‘[The Court]: You said thirty, you said thirty-five and
you said forty. Tell me where all of this is coming from
inside your head, please.
  ‘‘[The Petitioner]: Well, she said that—she gave me
the same thing, that the prosecutor wanted fifty, the
judge wanted I guess forty, and they was willing—he
asked for thirty or thirty-five years.’’
   To establish prejudice in a lapsed plea case, ‘‘a peti-
tioner need establish only that (1) it is reasonably proba-
ble that, if not for counsel’s deficient performance, the
petitioner would have accepted the plea offer, and (2)
the trial judge would have conditionally accepted the
plea agreement if it had been presented to the court.’’
Ebron v. Commissioner of Correction, 307 Conn. 342,
357, 53 A.3d 983 (2012), cert. denied sub nom. Arnone
v. Ebron, 569 U.S. 913, 133 S. Ct. 1726, 185 L. Ed. 2d
802 (2013).
   In the present action, the petitioner has established
that the trial judge would have accepted the plea
agreement, because the trial judge participated in pre-
trial conferences in which the court indicated what
offers it might accept.5 The petitioner, however, has
not established that it was reasonably probable that he
would have accepted the plea offer. As the habeas court
noted, ‘‘[r]egarding prejudice, nearly two decades later,
the petitioner has still not testified that he would have
accepted an offer in the thirty to forty year range, indi-
cating, ‘I don’t know.’ The twenty-five year sentence he
would have accepted was never available to him.’’ We
thus conclude that the habeas court’s finding that the
petitioner did not demonstrate prejudice was not
clearly erroneous.
                            II
   The petitioner next claims that he received ineffective
assistance of counsel because of the allegedly deficient
trial strategy employed by Silverstein in pursuing the
extreme emotional disturbance affirmative defense at
trial. The petitioner claims that Silverstein was deficient
in selecting and presenting this defense, and had he
consulted an expert prior to trial, he could have pre-
sented evidence to the jury that rose to the level of
extreme emotional disturbance. Alternatively, the peti-
tioner argues that an expert would have persuaded Sil-
verstein not to pursue the defense at all, specifically
stating, ‘‘[a]n expert could help develop the themes of
the defense, or inform the attorney if there is an actual
basis for the [extreme emotional disturbance] defense
to be asserted.’’ On this issue, the habeas court dis-
cussed both the performance and prejudice prongs of
Strickland in determining that the petitioner had not
met his burden to prove ineffective assistance of coun-
sel. We address each prong in turn.
   ‘‘To satisfy the performance prong [of the Strickland
test], 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.’’
(Internal quotation marks omitted.) Small v. Commis-
sioner of Correction, 286 Conn. 707, 713, 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). Inasmuch as
‘‘[c]onstitutionally adequate assistance of counsel
includes competent pretrial investigation’’; Siemon v.
Stoughton, 184 Conn. 547, 554, 440 A.2d 210 (1981);
‘‘[e]ffective assistance of counsel imposes an obligation
[on] the attorney to investigate all surrounding circum-
stances of the case and to explore all avenues that may
potentially lead to facts relevant to the defense of the
case.’’ (Internal quotation marks omitted.) Williams v.
Commissioner of Correction, 100 Conn. App. 94, 102,
917 A.2d 555, cert. denied, 282 Conn. 914, 924 A.2d
140 (2007).
   Similarly, the United States Supreme Court has
emphasized that a reviewing court is ‘‘required not sim-
ply to give [the trial attorney] the benefit of the doubt
. . . but to affirmatively entertain the range of possible
reasons . . . counsel may have had for proceeding as
[he] did . . . .’’ (Citations omitted; internal quotation
marks omitted.) Cullen v. Pinholster, 563 U.S. 170, 196,
131 S. Ct. 1388, 179 L. Ed. 2d 557 (2011). ‘‘[S]trategic
choices made after thorough investigation of law and
facts relevant to plausible options are virtually unchal-
lengeable; [but] strategic choices made after less than
complete investigation are reasonable precisely to the
extent that reasonable professional judgments support
the limitations 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. In any ineffectiveness case, a partic-
ular decision not to investigate must be directly
assessed for reasonableness in all the circumstances,
applying a heavy measure of deference to counsel’s
judgments.’’ (Internal quotation marks omitted.) Gaines
v. Commissioner of Correction, 306 Conn. 664, 680, 51
A.3d 948 (2012).
  The petitioner claims that Silverstein’s failure to call
an expert could not have been a reasonable tactical
decision because Silverstein failed to investigate the
usefulness of such an expert. We begin by noting that
there is no per se rule that requires a trial attorney to
seek out an expert witness. However, this court noted
that in some cases, ‘‘the failure to use any expert can
result in a determination that a criminal defendant was
denied the effective assistance of counsel.’’ (Internal
quotation marks omitted.) Stephen S. v. Commissioner
of Correction, 134 Conn. App. 801, 811, 40 A.3d 796,
cert. denied, 304 Conn. 932, 43 A.3d 660 (2012); see also
Lindstadt v. Keane, 239 F.3d 191, 201–202, 204 (2d
Cir. 2001) (holding that failure to consult an expert on
sexual abuse of children constituted inadequate assis-
tance). This court has also determined that ‘‘[t]he failure
of defense counsel to call a potential defense witness
does not constitute ineffective assistance unless there
is some showing that the testimony would have been
helpful in establishing the asserted defense.’’ (Internal
quotation marks omitted.) Eastwood v. Commissioner
of Correction, 114 Conn. App. 471, 481, 969 A.2d 860,
cert. denied, 292 Conn. 918, 973 A.2d 1275 (2009). There-
fore, the burden is on the petitioner to show that an
expert would have been necessary to establish the
extreme emotional disturbance defense in this case.
   The affirmative defense of extreme emotional distur-
bance, as described in State v. Elliot, 177 Conn. 1, 411
A.2d 3 (1979), allows the defendant to mitigate the
charge of murder to manslaughter if he can prove by
a fair preponderance of the evidence: ‘‘(a) the emotional
disturbance is not a mental disease or defect that rises
to the level of insanity as defined by the Penal Code;
(b) the defendant was exposed to an extremely unusual
and overwhelming state, that is, not mere annoyance
or unhappiness; and (c) the defendant had an extreme
emotional reaction to it, as a result of which there was
a loss of self-control, and reason was overborne by
extreme intense feelings, such as passion, anger, dis-
tress, grief, excessive agitation or other similar emo-
tions.’’ Id., 9.
   The habeas court determined that the petitioner had
not presented sufficient evidence ‘‘to establish a reason-
able probability that consultation with an expert or
presenting such an expert at trial would have been
helpful in asserting the [extreme emotional distur-
bance] defense.’’ Furthermore, the court found that Sil-
verstein’s decision not to retain an expert witness in
pursuing the extreme emotional disturbance defense
was a reasonable strategic decision. Silverstein’s testi-
mony indicated that he made a strategic decision in
choosing to pursue the extreme emotional disturbance
defense through the testimony of the petitioner and lay
witnesses, rather than an expert witness. Silverstein
testified that he did not find evidence of a clinical psy-
chological issue, stating that ‘‘[the petitioner] never
made me aware of any background that he had suffered
from any type of [psychological issues] . . . . He told
me he was depressed, but it was about the relationship.
It wasn’t independent of the relationship.’’ From speak-
ing with many people who knew the petitioner, Sil-
verstein learned that ‘‘he was in love with a woman
who didn’t love him, who was seeing other people, who
had a child that he had a very close bond with, who he
took care of, and that, in my mind, you know, he couldn’t
control the jealousy, the rage, the anger he was feeling
towards her.’’ On the basis of these interviews, Sil-
verstein determined that he did not believe it would be
prudent to call an expert witness when the petitioner
and lay witnesses could testify to the same evidence.
   Silverstein was also concerned that the jury would
look unfavorably on an expert who was paid to testify
on the petitioner’s behalf. He testified, ‘‘I had a way,
an idea how I was going to argue the case, and putting an
expert up there who I’d pay to say that he is depressed
is not going to help me or [the petitioner], in my mind.
. . . [I]f you’re calling an expert in on a psychological
type of thing or to testify about extreme emotional
distress . . . they know I’m paying them. Their conclu-
sions are, you know, if not borne out by the facts,
don’t really help and it gives the state’s attorney an
opportunity to get up there and say, you know: He calls
in an expert who’s now going to tell you that he acted
under extreme emotional distress. He paid this expert.
The expert saw him nine months after the incident.
What else is the expert going to say?’’ On the basis of
this testimony, the habeas court properly found that
it was not objectively unreasonable for Silverstein to
choose not to call an expert for the extreme emotional
disturbance defense.
  The court’s determination of reasonableness is also
supported by the record, specifically, the testimony of
Dinnan and Brown. When asked if the petitioner had
presented an expert in support of his extreme emotional
disturbance defense, Dinnan testified, ‘‘I don’t recall any
expert, which isn’t unusual for that particular defense.’’
When the court questioned him further on this, Dinnan
responded: ‘‘That’s just my experience. They put on
the facts surrounding it, the history of the particular
relationship, and that’s . . . again, that’s what I recall
happening in this particular case.’’ Furthermore, the
habeas court was not persuaded by the testimony of
the petitioner’s expert, Brown, as he stated it was unrea-
sonable for Silverstein to fail to consult an expert in
this case, but admitted that he had never raised the
defense at trial and had only used it during pretrial
negotiations to advocate for a better deal for his client.6
  The petitioner also claims that the defense itself was
an unreasonable trial strategy, and that if Silverstein
had consulted with an expert, he may not have pursued
the defense at all. But, as Silverstein testified, ‘‘it was
the only defense he had,’’ based on the strength of the
evidence against the petitioner and the state’s unwilling-
ness to reduce the charge from murder to manslaughter.
Facing this scenario, the habeas court found that Sil-
verstein’s decision to move forward with the extreme
emotional disturbance defense was a ‘‘necessity, com-
pelled by an offer of an unacceptably lengthy prison
term based on compelling evidence of guilt.’’ Therefore,
we conclude that the habeas court’s finding that ‘‘the
defense presented by underlying counsel was not unrea-
sonable in light of all of the evidence’’ was not
clearly erroneous.
  Even if Silverstein was deficient in his performance
by failing to consult with an expert on the extreme
emotional disturbance defense, the petitioner did not
show that this allegedly deficient performance preju-
diced him. ‘‘It is well established that a petitioner in a
habeas proceeding cannot rely on mere conjecture or
speculation to satisfy either the performance or preju-
dice prong but must instead offer demonstrable evi-
dence in support of his claim.’’ (Internal quotation
marks omitted.) Lopez v. Commissioner of Correction,
142 Conn. App. 53, 59, 64 A.3d 334 (2013); see also
Crawford v. Commissioner of Correction, 285 Conn.
585, 599, 940 A.2d 789 (2008) (petitioner’s burden not
met by speculation but by demonstrable realities); Nar-
umanchi v. DeStefano, 89 Conn. App. 807, 815, 875 A.2d
71 (2005) (‘‘[s]peculation and conjecture have no place
in appellate review’’).
   We conclude that the petitioner has failed to demon-
strate that there is a reasonable probability that if Sil-
verstein had consulted with or called an expert witness
during the criminal trial, the jury would have had rea-
sonable doubt as to the petitioner’s guilt. The petitioner
has simply speculated that the result might have been
different had Silverstein chosen to utilize an expert
witness. We also note the substantial evidence in the
record that would support the jury’s guilty verdict. Spe-
cifically, the victim and the petitioner had a long history
of domestic violence incidents, and witnesses testified
at trial that the victim screamed in terror as the peti-
tioner pursued her before shooting her five times at
close range. State v. Kellman, supra, 56 Conn. App.
281. The petitioner subsequently confessed to firing
the shots that killed the victim to numerous people,
including members of the New Haven Police Depart-
ment. On the basis of the strength of the evidence pre-
sented to the jury, we conclude that the petitioner has
not met his burden of showing that the jury verdict
might have been different without counsel’s allegedly
deficient performance.
  On the basis of our review of the record, we hold
that the court’s factual findings and legal conclusions
are sufficiently supported by the record. We therefore
hold that the court did not err in determining that the
petitioner failed to prove ineffective assistance of coun-
sel. Accordingly, we conclude that the court properly
denied the petition for a writ of habeas corpus.
  The judgment is affirmed.
      In this opinion the other judges concurred.
  1
     While the habeas pleadings refer to the petitioner as ‘‘Carmine,’’ the
petitioner testified at the habeas trial that his first name is ‘‘Carmi,’’ and
this court’s direct appeal decision refers to him as ‘‘Carmi.’’ See State v.
Kellman, 56 Conn. App. 279, 742 A.2d 423, cert. denied, 252 Conn. 939, 747
A.2d 4 (2000).
   2
     The petitioner was also acquitted of one count of stalking in the first
degree in violation of General Statutes § 53a-181c (a) (2).
   3
     The petitioner’s amended habeas petition also included a claim of ineffec-
tive assistance of counsel regarding failure to apply for sentence review,
but that issue has not been raised on appeal.
   4
     Rosenblum was initially appointed to represent the petitioner at the time
of his arraignment, but he became ill and was replaced by Silverstein prior
to trial. Carpenter represented the petitioner in his first habeas petition,
filed in 2011.
   5
     At the habeas trial, Dinnan testified that Judge Damiani conducted pre-
trial negotiations and made an offer that he indicated he would accept,
stating in relevant part that ‘‘[t]he procedure that occurred is we had a
pretrial conference with Judge . . . I believe it was Judge Damiani. I had
made an offer of fifty years that would encompass all the charges. . . .
Judge Damiani indicated he would do forty years to encompass all the
charges, and then . . . Rosenblum went downstairs into the lockup to dis-
cuss the matter with [the petitioner], and it was not accepted.’’
   6
     During the habeas proceeding, the following exchange occurred between
the respondent’s counsel and Brown:
   ‘‘[The Respondent’s Counsel]: Do you recall when about the first case
was that you raised an [extreme emotional disturbance] defense?
   ‘‘[Brown]: Oh, I mean, the first case would have been . . . . I don’t recall
exactly. . . . A couple of them I can tell you I know I hired an expert, and
the expert basically said there’s nothing here, so I just kind of tried to bluff
my way through it and get a better deal, but, so those weren’t all that went
to trial or anything like that.
   ‘‘[The Respondent’s Counsel]: Okay. So these were potential defenses that
you were exploring pretrial?
   ‘‘[Brown]: Correct. Correct.
   ‘‘[The Respondent’s Counsel]: How many extreme emotional disturbance
defenses did you raise at—have you raised at trial?
   ‘‘[Brown]: At trial—well, I’ve only raised them at pretrial. I haven’t raised
them at trial, and we’ve been able to work it out once we disclose the
expert report.’’
