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 ERIC WHITE v. COMMISSIONER OF CORRECTION
                  (AC 39783)
               DiPentima, C. J., and Sheldon and Harper, Js.

                                    Syllabus

The petitioner, who had been convicted on a guilty plea of the crime of
    felony murder, sought a writ of habeas corpus, claiming that his right
    to due process was violated because his guilty plea was not made
    knowingly, intelligently and voluntarily, and that his trial counsel pro-
    vided ineffective assistance by failing to adequately research and investi-
    gate the issue of his mental state at the time of his guilty plea and to
    bring that information to the trial court’s attention. Specifically, the
    petitioner claimed that the medication he was taking on the day of his
    guilty plea substantially impacted his ability to understand the plea
    agreement and proceedings. The habeas court rendered judgment deny-
    ing the habeas petition, from which the petitioner, on the granting of
    certification, appealed to this court. Held:
1. The habeas court did not err in failing to find that the petitioner’s due
    process rights were violated; that court found that the petitioner’s guilty
    plea canvass was constitutionally sufficient, as the petitioner had denied
    taking any drugs, alcohol or medication the day of the plea canvass and
    indicated that he had discussed his case with his counsel, and that the
    petitioner had acknowledged at sentencing that he had taken medication
    for the purpose of falling asleep and gave no indication that he wanted
    to withdraw his plea, the habeas court’s findings were adequately sup-
    ported by the record, which showed that the petitioner’s responses to
    the trial court’s questions during his canvass demonstrated that he fully
    understood the circumstances, and although the habeas court did not
    completely discredit the petitioner’s testimony at the habeas trial that
    he had taken medication at the time of his guilty plea, that it made him
    feel like a zombie and that he lied about not taking medication at the
    plea hearing because he thought it would help him, it did not specifically
    credit anything to which he testified, and it was not for this court,
    in deciding whether the petitioner’s guilty plea was made knowingly,
    intelligently and voluntarily, to discard the habeas court’s credibility
    determination that the evidence bordered on frivolous and was insuffi-
    cient to prove a due process violation.
2. The habeas court did not err in concluding that the petitioner’s trial
    counsel did not render ineffective assistance: that court credited trial
    counsel’s testimony as to his numerous visits and discussions with the
    petitioner, that it was clear that the petitioner understood what he was
    doing, and that he had no concerns regarding the petitioner’s mental
    state, and in light of that testimony and because the record did not evince
    that the petitioner was actually impaired by the use of any medication,
    his trial counsel was not deficient for failing to investigate the petitioner’s
    mental health further or to bring his mental state to the attention of the
    court; moreover, even if trial counsel’s performance was deficient, the
    record did not show a reasonable probability that the petitioner would
    have chosen to proceed to trial rather than plead guilty if trial counsel
    had further investigated the petitioner’s mental state or brought it to
    the trial court’s attention.
             Argued March 19—officially released May 22, 2018

                              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; thereafter, the court granted the
petition for certification to appeal, and the petitioner
appealed to this court. Affirmed.
   Michael W. Brown, for the appellant (petitioner).
  Linda F. Currie-Zeffiro, assistant state’s attorney,
with whom were John C. Smriga, state’s attorney, and
Emily Trudeau, assistant state’s attorney, for the appel-
lee (respondent).
                          Opinion

   HARPER, J. The petitioner, Eric White, appeals from
the judgment of the habeas court denying his amended
petition for a writ of habeas corpus. On appeal, the
petitioner claims that the court improperly rejected his
claims that (1) his right to due process was violated
because his guilty plea was not made knowingly, intelli-
gently and voluntarily and (2) his right to effective assis-
tance of counsel was violated because his attorney
failed to adequately research and investigate the issue
of the petitioner’s mental state at the time of his guilty
plea and to bring information about the petitioner’s
compromised mental state to the attention of the crimi-
nal trial court. We disagree and, accordingly, affirm the
judgment of the habeas court.
  The following facts and procedural history are rele-
vant to this appeal. On August 11, 2004, the petitioner,
represented by Attorney Joseph Bruckmann, pleaded
guilty under the Alford1 doctrine to one count of felony
murder in violation of General Statutes §§ 53a-54c and
53a-54a (a). The trial court indicated that it intended to
sentence the petitioner to fifty years of imprisonment,
which it did on November 5, 2004. The petitioner did
not appeal from his conviction following his plea and
sentencing or file any postjudgment motions.
   The petitioner petitioned for a writ of habeas corpus
on January 8, 2014. After counsel was appointed, the
petitioner filed an amended petition on May 23, 2016,
asserting that Bruckmann had provided ineffective
assistance of counsel and that the petitioner’s due pro-
cess rights had been violated because his guilty plea
was not made knowingly, intelligently and voluntarily.
The thrust of his claims was that medication the peti-
tioner was taking on the day of his guilty plea ‘‘substan-
tially impacted his ability to understand the plea
agreement and the plea proceedings,’’ that he would
not have entered a guilty plea had he not been so medi-
cated, and that Bruckmann was ineffective for failing to
research and investigate the issue regarding his mental
condition or to bring such information to the court’s
attention. (Internal quotation marks omitted.)
  At the habeas trial on September 19, 2016, Bruck-
mann, the petitioner, and the petitioner’s psychiatric
expert, James Phillips, testified. The petitioner also
entered into evidence the transcripts of his guilty plea
and sentencing, and medical records detailing his medi-
cation usage around the time of his guilty plea. The
respondent, the Commissioner of Correction, offered
no evidence.
  On September 27, 2016, the habeas court issued its
memorandum of decision denying the amended petition
for a writ of habeas corpus. The court credited the
testimony of Bruckmann and Phillips in determining
that the petitioner had failed to establish ineffective
assistance of counsel or a due process violation.2 In
evaluating the transcripts in evidence, the court
observed that Bruckmann and the trial court made the
petitioner aware ‘‘of all necessary information to make
an informed decision . . . whether to enter a plea or
take his case to trial.’’ In considering the petitioner’s
own testimony, although the habeas court did not find
that testimony completely lacking in credibility, it found
that such testimony was ‘‘wholly insufficient to prove
any of the necessary elements to establish either a due
process violation or a claim of ineffective assistance
of counsel. Contrasted with the other, more credible
evidence adduced at trial, the petitioner’s proffered evi-
dence in support of his claims borders on the frivolous.’’
  The petitioner petitioned the habeas court for certifi-
cation to appeal, which the court granted. This
appeal followed.
   We begin with generally applicable legal principles.
‘‘The underlying historical facts found by the habeas
court may not be disturbed unless the findings were
clearly erroneous. . . . Historical facts constitute a
recital of external events and the credibility of their
narrators. . . . Questions of law and mixed questions
of law and fact receive plenary review.’’ (Internal quota-
tion marks omitted.) Crawford v. Commissioner of
Correction, 294 Conn. 165, 174, 982 A.2d 620 (2009).
‘‘The application of the habeas court’s factual findings
to the pertinent legal standard . . . presents a mixed
question of law and fact . . . .’’ Duperry v. Solnit, 261
Conn. 309, 335, 803 A.2d 287 (2002).
                             I
   The petitioner first claims that the habeas court erred
in failing to find that his due process rights were violated
because his underlying guilty plea was not made know-
ingly, intelligently and voluntarily. Specifically, he
argues that the medication he was taking at the time
of his guilty plea ‘‘completely undermined his ability to
meaningfully consider his decision to plead guilty [and]
interfered with his ability to understand the plea
agreement and the guilty plea proceeding.’’ We disagree.
   ‘‘[T]he guilty plea and subsequent conviction of an
accused person who is not legally competent to stand
trial violates the due process of law guaranteed by the
state and federal constitutions. . . . This constitu-
tional safeguard, which is codified at General Statutes
§ 54-56d (a), provides that [a] defendant shall not be
tried, convicted or sentenced while the defendant is
not competent. . . . [A] defendant is not competent if
the defendant is unable to understand the proceedings
against him or her or to assist in his or her own
defense. . . .
  ‘‘[T]he test for competency must be whether [the
defendant] has sufficient present ability to consult with
his lawyer with a reasonable degree of rational under-
standing—and whether he has a rational as well as
factual understanding of the proceedings against him.
. . .
   ‘‘Although § 54-56d (b) presumes the competency of
defendants, when a reasonable doubt concerning the
defendant’s competency is raised, the trial court must
order a competency examination. . . . Thus, [a]s a
matter of due process, the trial court is required to
conduct an independent inquiry into the defendant’s
competence whenever he makes specific factual allega-
tions that, if true, would constitute substantial evidence
of mental impairment. . . . Evidence is substantial if
it raises a reasonable doubt about the defendant’s com-
petency . . . .
   ‘‘[D]ue process requires that a plea be entered volun-
tarily and intelligently. . . . Because every valid guilty
plea must be demonstrably voluntary, knowing and
intelligent, we require the record to disclose an act that
represents a knowing choice among available alterna-
tive courses of action, an understanding of the law in
relation to the facts, and sufficient awareness of the
relevant circumstances and likely consequences of the
plea. . . . A determination as to whether a plea has
been knowingly and voluntarily entered entails an
examination of all of the relevant circumstances. . . .
A defendant who suffers from a mental or emotional
impairment is not necessarily incompetent to enter a
guilty plea because [c]ompetence . . . is not defined
in terms of mental illness. An accused may be suffering
from a mental illness and nonetheless be able to under-
stand the charges against him and to assist in his own
defense . . . . Similarly, [t]he fact that the defendant
was receiving medication . . . [of itself] does not ren-
der him incompetent. . . . The touchstone of compe-
tency, rather, is the ability of the defendant to
understand the proceedings against him and to assist
in his own defense.’’ (Citations omitted; footnotes omit-
ted; internal quotation marks omitted.) Taylor v. Com-
missioner of Correction, 284 Conn. 433, 449–52, 936
A.2d 611 (2007).
   The habeas court found no due process violation. In
its memorandum of decision, the habeas court first
found that the petitioner’s guilty plea canvass was con-
stitutionally sufficient, noting that the petitioner had
denied having taken any drugs, alcohol, or medication
that day. The court also noted that the petitioner indi-
cated at his plea proceeding that he and Bruckmann had
discussed the case, including the underlying elements
of the charges. The habeas court also observed that the
trial court had indicated the sentence it intended to
impose on a later date. The petitioner reaffirmed his
understanding of the decision to plead guilty and accept
a fifty year sentence.
  The habeas court also considered the transcript of the
petitioner’s sentencing, where the petitioner accepted
responsibility for his actions and acknowledged that
‘‘fifty years is not enough’’ for his offense. (Internal
quotation marks omitted.) The petitioner gave no indi-
cation that he wanted to withdraw his plea. The peti-
tioner did acknowledge taking medication at the time,
but stated that it was for the purpose of falling asleep.
   At the habeas trial, the petitioner testified that he
was taking medication at the time of his guilty plea,
although he could not recall what he was taking. He
also testified that he continued taking medication until
about six to eight months after he was sentenced, hav-
ing taken himself off it because it ‘‘made [him] feel like
[he] wasn’t in the right state of mind half the time’’ and
‘‘a robot, a zombie . . . .’’ He claimed that these feel-
ings affected his decision-making at and before the time
he pleaded guilty because he did not always understand
Bruckmann in their conversations before the plea.3
   When the petitioner was asked why he denied taking
any medication on the day of his plea, the petitioner
claimed that he did not want to seem ‘‘insane’’ to the
trial judge and that answering affirmatively would only
have harmed him. Then, in response to a question
regarding why he had pleaded guilty, the petitioner
stated, ‘‘I [pleaded] guilty to benefit my family and to
keep any more harm coming upon my family, so I just
said, I understand and I [pleaded] guilty. I wanted to
plead guilty to get it over with. Those were my exact
words to [Attorney] Bruckmann. I want to get it over
with to keep my mother from going through what she
was going through.’’ The petitioner then claimed that
the medication he was taking affected these feelings.
Finally, when asked why he was challenging his convic-
tion almost ten years after his plea, he stated, ‘‘[w]ell,
due to the fact that I’ve been incarcerated for fourteen
years now and . . . I had time to think about every-
thing that happened . . . and due to the fact that I’m
older and I just feel like . . . I have nothing to really
lose from wanting my freedom back, and also my fam-
ily.’’ The petitioner then denied having waited ten years
for evidence to be destroyed.
   On cross-examination, the petitioner was asked again
why he waited ten years to challenge his plea. He
responded that he was scared and did not understand
the law at the time. Counsel for the respondent then
asked when the petitioner became aware that his medi-
cation was an issue. The petitioner responded that he
became aware of that issue after sentencing. Finally,
when asked why he had lied about not taking medica-
tion at his plea hearing, the petitioner said, ‘‘I thought
it would help.’’
   We conclude that the habeas court’s findings are sup-
ported more than adequately by the record. The peti-
tioner’s responses to the trial court’s questions during
his canvass show that he fully understood the circum-
stances. ‘‘A court may properly rely on . . . the
responses of the [petitioner] at the time [he] responded
to the trial court’s plea canvass . . . .’’ (Internal quota-
tion marks omitted.) Bigelow v. Commissioner of Cor-
rection, 175 Conn. App. 206, 215–16, 167 A.3d 1054,
cert. denied, 327 Conn. 929, 171 A.3d 455 (2017). The
petitioner’s claim that he felt like a ‘‘zombie’’ and not
in control of his actions is not borne out by the tran-
scripts of the plea proceeding. Because the petitioner’s
expert offered no opinion as to the petitioner’s mental
state at the time of his plea; see footnote 3 of this
opinion; the only evidence that could establish that the
petitioner was not lucid at the time of his plea is his
own testimony.4 Although the habeas court did not com-
pletely discredit the petitioner’s testimony, it did not
specifically credit anything to which he testified, stating
instead that his evidence ‘‘border[ed] on the frivolous,’’
and was insufficient to prove a due process violation.5
We are not at liberty to discard this credibility determi-
nation in deciding whether the petitioner’s guilty plea
was made knowingly, intelligently and voluntarily. The
burden was on the petitioner to establish ‘‘a reasonable
likelihood that the medication had adversely affected
the petitioner’s ability to understand the proceedings
against him or to assist in his own defense.’’ Taylor v.
Commissioner of Correction, supra, 284 Conn. 453. In
the absence of any other convincing evidence to the
contrary, we cannot say that the habeas court erred in
not finding the relevant facts to establish a due pro-
cess violation.
                             II
   The petitioner also claims that the habeas court erred
in not determining that his trial counsel provided inef-
fective assistance. Specifically, the petitioner argues
that Bruckmann failed to research adequately and to
investigate the issue of the petitioner’s mental state at
the time of his guilty plea, and to bring information
about the petitioner’s compromised mental state to the
attention of the trial court. We are not persuaded.
   ‘‘To prevail on a constitutional claim of ineffective
assistance of counsel resulting from a guilty plea, a
petitioner must establish both that his counsel’s perfor-
mance was deficient and that the deficient performance
prejudiced him. See Hill v. Lockhart, 474 U.S. 52, 106
S. Ct. 366, 88 L. Ed. 2d 203 (1985); Strickland v. Wash-
ington, 466 U.S. 668, 687, 104 S. Ct. 2052, 80 L .Ed. 2d
674 (1984); Baillargeon v. Commissioner of Correction,
67 Conn. App. 716, 721, 789 A.2d 1046 (2002). To satisfy
the performance prong, the petitioner must show that
counsel’s representation fell below an objective stan-
dard of reasonableness. . . . To satisfy the prejudice
prong, the petitioner must show a reasonable probabil-
ity that, but for counsel’s errors, he would not have
pleaded guilty and would have insisted on going to trial.
. . . A reviewing court can find against a petitioner on
either ground, whichever is easier. . . . The petitioner
cannot rely on mere conjecture or speculation to satisfy
either the performance or prejudice prong but must
instead offer demonstrable evidence in support of his
claim.’’ (Internal quotation marks omitted.) Cox v. Com-
missioner of Correction, 127 Conn. App. 309, 314, 14
A.3d 421, cert. denied, 301 Conn. 902, 17 A.3d 1043
(2011).
   The habeas court, in its memorandum of decision,
found that the petitioner failed to establish that Bruck-
mann rendered ineffective assistance. The court cred-
ited Bruckmann’s testimony as to his numerous visits
and discussions with the petitioner. Bruckmann had
also testified that the petitioner wanted to enter the
plea and accept his sentence and that it was clear to
Bruckmann that the petitioner understood what he was
doing, such that Bruckmann perceived no ‘‘red flags’’
concerning the petitioner’s mental state. (Internal quo-
tation marks omitted.) In addition, Bruckmann engaged
the services of a forensic psychiatrist to evaluate the
petitioner for any potential defenses to his murder
charge. Bruckmann indicated that the psychiatrist
reported no signs of psychosis or that the petitioner’s
mental health was an issue.
   The petitioner argues that he was prejudiced because
he would not have pleaded guilty but for Bruckmann’s
failure to adequately research and investigate the peti-
tioner’s mental state. He also argues that he was preju-
diced because the trial court would not have accepted
his guilty plea had Bruckmann not failed to bring to the
attention of the trial court the petitioner’s compromised
mental state.6 His prejudice arguments necessarily
depend on his argument that his mental state was com-
promised at the time of his pleas, which we determined
was not borne out by the record in the context of his
due process claim. See part I of this opinion. We like-
wise reject that argument underlying these claims of
ineffective assistance. ‘‘Because the record before us
does not evince that the petitioner was actually
impaired by the use of any psychotropic drugs, we can-
not conclude that his counsel was deficient in failing
to investigate his mental . . . health further.’’ Hunni-
cutt v. Commissioner of Correction, 83 Conn. App. 199,
207, 848 A.2d 1229, cert. denied, 270 Conn. 914, 853
A.2d 527 (2004). Given Bruckmann’s credited testimony
that he perceived no ‘‘red flags,’’ we likewise cannot
conclude that Bruckmann was deficient for failing to
bring the petitioner’s mental state to the attention of
the court, because such testimony is contraindicative
of ‘‘a reasonable doubt concerning the [petitioner’s]
competency . . . .’’ Taylor v. Commissioner of Cor-
rection, supra, 284 Conn. 450. Even if we assume defi-
cient performance, the record does not show ‘‘a
reasonable probability that [the petitioner] would have
chosen to proceed to trial rather than plead guilty’’
if Bruckmann had further investigated the petitioner’s
mental state or brought it to the trial court’s attention.
Hunnicutt v. Commissioner of Correction, supra, 210.
Therefore, the habeas court did not err in concluding
that Bruckmann did not render ineffective assistance
of counsel.
      The judgment is affirmed.
      In this opinion the other judges concurred.
  1
     North Carolina v. Alford, 400 U.S. 25, 91 S. Ct. 160, 27 L. Ed. 2d 162 (1970).
  2
     Phillips called the petitioner’s dosage of lithium that he took the day of
his plea ‘‘fairly standard.’’ Additionally, the court noted that ‘‘[Phillips] testi-
fied that he could not render an expert opinion on the petitioner’s ability,
twelve years ago, to enter a voluntary, knowing and intelligent plea, as there
were too many unknowns . . . .’’
   3
     Phillips stated that the petitioner’s dosage of lithium on the day of his
plea was ‘‘fairly standard’’ and testified as to some of lithium’s and Remeron’s
side effects, but offered no opinion as to the petitioner’s mental state at the
time of his plea.
   4
     The petitioner argues that his medication records also are indicative of
his mental state at the time of his guilty plea. Without testimony from Phillips
that such medication was reasonably likely to have caused negative effects
on the petitioner’s willpower at the time of the plea, we are not convinced
that these medical records have much probative value.
   5
     To the extent that his testimony could be credited, the petitioner testified
to choosing to plead guilty to avoid problems for his family and not telling
the court that he was on medication to avoid appearing ‘‘insane,’’ both of
which would tend toward the type of lucidity inherent in someone making
a knowing, intelligent and voluntary guilty plea.
   6
     The petitioner argues ‘‘that the trial court had an independent duty to
assess the petitioner’s mental state at the time of his guilty plea,’’ but provides
no legal authority to support this proposition. Rather, we consider whether
the petitioner would have pleaded guilty but for Bruckmann’s failure to
notify the court of the petitioner’s compromised mental state. See Cox v.
Commissioner of Correction, supra, 127 Conn. App. 314.
