                    FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

CRAIG CLIFFORD BUSCH,                     
               Petitioner-Appellant,
                 v.
                                                 No. 06-16154
JEANNE S WOODFORD, in her
capacity as Director of the                       D.C. No.
                                                CV-04-04157-MJJ
California Department of
Corrections; JOSEPH L. MCGRATH,                    OPINION
Warden, in his capacity as
Warden, Pelican Bay State Prison,
            Respondents-Appellees.
                                          
         Appeal from the United States District Court
           for the Northern District of California
          Martin J. Jenkins, District Judge, Presiding

                   Argued and Submitted
        February 15, 2007—San Francisco, California

                      Filed August 29, 2007

    Before: J. Clifford Wallace, Richard D. Cudahy,* and
          M. Margaret McKeown, Circuit Judges.

                    Opinion by Judge Cudahy




   *The Honorable Richard D. Cudahy, Senior United States Circuit Judge
for the Seventh Circuit, sitting by designation.

                                10881
10884                  BUSCH v. WOODFORD


                           COUNSEL

Donald L. Lipmanson, Ukiah, California, for the petitioner-
appellant.

Dorian Jung, Office of the Attorney General, State of Califor-
nia, San Francisco, California, for the respondent-appellee.


                           OPINION

CUDAHY, Circuit Judge:

   In 1998, the petitioner, Craig Busch, pleaded guilty to first
degree murder. Busch filed a petition for writ of habeas cor-
pus in the California state trial court alleging ineffective assis-
tance of counsel and that his plea was not voluntary and
intelligent. After holding a three-day evidentiary hearing, the
state court denied the petition without opinion. The California
Court of Appeal and the California Supreme Court also sum-
                         BUSCH v. WOODFORD                        10885
marily denied the petition. Busch then filed the present peti-
tion in the Northern District of California. The district court
denied the petition but issued a certificate of appealability as
to the voluntariness of the plea given the length of time the
petitioner had to consider the proposed plea agreement. The
petitioner appeals the denial of the petition and raises uncerti-
fied issues concerning ineffective assistance of counsel as
well. We decline to expand the certificate of appealability and
affirm the denial of the petition as to the certified issue.

      FACTUAL AND PROCEDURAL BACKGROUND

   On the morning of February 2, 1997, Petitioner Craig
Busch was allegedly angry with George Steven Wilson
because Wilson had moved out of the petitioner’s family ranch.1
Busch told a number of people that he had decided to kill Wil-
son. Wilson was last seen alive that evening with Busch and
Busch’s companions, Donovan Williams and Dillon Bacon.
When Busch, Williams and Bacon were seen later that eve-
ning without Wilson, they reported that his truck had become
stuck in the mud and that Wilson had stayed behind with it.

   Wilson was later found dead near his truck with three bullet
wounds in his head. Busch had previously identified the place
where Wilson’s body was found as a good place to carry out
a murder. Busch was subsequently taken into custody. While
incarcerated, a jailhouse informant reported that Busch had
told him where Busch had hidden the murder weapon. A gun
was subsequently recovered at that location, and ballistics
tests confirmed that it had been used in the killing.

  On May 12, 1997, the Lake County District Attorney filed
an information charging Busch with first degree murder pur-
suant to California Penal Code § 187(a). The information also
  1
  The facts are derived from the decision of the California Court of
Appeal, First Appellate Division, denying Busch’s direct appeal. Case No.
A083099 (filed Oct. 12, 1999). These facts are not disputed.
10886                    BUSCH v. WOODFORD
included enhancements for: personal use of a firearm in the
commission of the first degree murder charge pursuant to Cal-
ifornia Penal Code § 1203.06(a)(1)(A); being armed in the
commission of the charged felony pursuant to California
Penal Code § 12022.5(a); and personal infliction of great bod-
ily injury pursuant to California Penal Code § 1203.075(a)(1).

   Busch’s trial began with jury selection on March 17, 1998.
On that same day, Busch gave a statement to police detectives
from the Lake County Sheriff’s Office. In the statement,
Busch reported that he witnessed Donovan Williams, one of
the other individuals with Wilson the night of his murder,
shoot Wilson in the head three times. He further reported that
Williams had given him the murder weapon to dispose of.

   On March 19, 1998, after the jury had been empaneled,
Busch’s trial counsel and the prosecutor asked the court to
delay opening arguments to allow them time to discuss a plea
arrangement. (See Petitioner’s ER at 63-64.) The court agreed
and allowed a two-hour recess until 4:30 that afternoon.
Shortly before 5:00 p.m., Busch’s trial counsel informed the
court that they had reached a resolution. Busch then entered
a negotiated plea of guilty to a charge of first degree murder
pursuant to People v. West.2 Pursuant to the plea agreement,
the enhancements were dismissed, a case against Busch con-
cerning an unrelated drug charge was also dismissed and the
prosecution agreed to not pursue a possible burglary charge
involving the suspected murder weapon or any perjury
charges against Busch’s girlfriend. On April 13, 1998, Busch
was sentenced to prison for an indeterminate term of 25 years
to life.

  On March 30, 2000, Busch filed a petition for habeas cor-
pus in the Superior Court of Lake County. In May of 2001,
  2
   People v. West, 477 P.2d 409 (Cal. 1970) does not require an admis-
sion of guilt and is the California equivalent of an Alford plea. See North
Carolina v. Alford, 400 U.S. 25 (1970).
                      BUSCH v. WOODFORD                    10887
the court held a three-day evidentiary hearing on the habeas
petition. On June 6, 2001, the court denied the petition with-
out opinion. The petition was also summarily denied by the
California Court of Appeal, First Appellate District Division
and by the California Supreme Court. On September 30,
2004, Busch filed the present federal petition for writ of
habeas corpus. The district court denied the petition but
granted a certificate of appealability as to one issue: whether
the petitioner’s plea agreement was involuntary in light of the
fact he was allowed only two hours to accept or reject it.

                 STANDARD OF REVIEW

   The Antiterrorism and Effective Death Penalty Act of 1996
(“AEDPA”) governs our review of Busch’s petition for writ
of habeas corpus. Relevant for this review, a federal court can
grant a state prisoner’s petition for a writ of habeas corpus if
the state court’s decision: 1.) was “contrary to . . . clearly
established Federal law, as determined by the Supreme Court
of the United States”; or 2.) “involved an unreasonable appli-
cation of . . . clearly established Federal law, as determined
by the Supreme Court of the United States.” 28 U.S.C.
§ 2254(d)(1).

   A state court’s decision is “contrary to” clearly established
federal law “if the state court arrives at a conclusion opposite
to that reached by [the Supreme Court] on a question of law
or if the state court decides a case differently than [the
Supreme Court] has on a set of materially indistinguishable
facts.” Williams v. Taylor, 529 U.S. 362, 412-13 (2000). As
for “unreasonable application,” a federal court may grant
relief “if the state court identifies the correct governing legal
principle from [the Supreme Court’s] decisions but unreason-
ably applies that principle to the facts of the prisoner’s case.”
Id. at 413. When a claim falls under the “unreasonable appli-
cation” clause, the state court’s application of the Supreme
Court precedent must be “objectively unreasonable,” not just
incorrect. Wiggins v. Smith, 539 U.S. 510, 520-21 (2003).
10888                 BUSCH v. WOODFORD
   Where the state court provides no basis for its decision to
deny a habeas corpus petition, as is the case here, the state
court decision does “not warrant the deference we might usu-
ally apply.” Delgado v. Lewis (Delgado II), 223 F.3d 976, 982
(9th Cir. 2000) (citing Delgado v. Lewis (Delgado I), 168
F.3d 1148, 1152 (9th Cir. 1999)). Lacking a reasoned opinion
from the state court, we review the record independently for
clear error of the state court ruling on the petition:

     [A]lthough we cannot undertake our review by ana-
     lyzing the basis for the state court’s decision, we can
     view it through the “objectively reasonable” lens
     ground by Williams. . . . Federal habeas review is not
     de novo when the state court does not supply reason-
     ing for its decision, but an independent review of the
     record is required to determine whether the state
     court clearly erred in its application of controlling
     federal law. Only by that examination may we deter-
     mine whether the state court’s decision was objec-
     tively reasonable.

Id. at 982 (internal citation omitted); see also Lewis v. Mayle,
391 F.3d 989, 996 (9th Cir. 2004).

                        DISCUSSION

I.   Scope of the Certificate of Appealability

   [1] The district court certified only the issue whether
Busch’s plea was involuntary in light of the fact he was
allowed only two hours to accept or reject it. In his opening
brief, the petitioner also raised the other issue in his habeas
petition under the heading of “Uncertified Issue.” We con-
strue this inclusion and designation as a motion to expand the
Certificate of Appealability (“COA”). 9th Cir. R. 22-1(e).

  [2] “The required showing for originally obtaining a COA
on a claim remains the standard by which this court reviews
                      BUSCH v. WOODFORD                    10889
the broadening of a COA. A habeas petitioner’s assertion of
a claim must make a ‘substantial showing of the denial of a
constitutional right.’ ” Hiivala v. Wood, 195 F.3d 1098, 1104
(9th Cir. 1999) (quoting 28 U.S.C. § 2253(c)(2)). In order to
make this showing, a petitioner “must demonstrate that the
issues are debatable among jurists of reason; that a court
could resolve the issues [in a different manner]; or that the
questions are adequate to deserve encouragement to proceed
further.” Barefoot v. Estelle, 463 U.S. 880, 893 n.4 (1983)
(alteration in original, internal quotation marks omitted);
accord Slack v. McDaniel, 529 U.S. 473, 484 (2000).

   The uncertified issue here involves ineffective assistance of
counsel. Busch posits two grounds for the appeal of this issue.
First, Busch argues that his attorneys were deficient in failing
to investigate potential mental defenses. Second, Busch con-
tends that his attorneys’ decision to allow him to be inter-
viewed by the Lake County Sheriff’s Office constitutes
ineffective assistance of counsel. He further argues that he
was prejudiced by the ineffectiveness of counsel since he
would have gone to trial rather than plead guilty. The district
court denied relief as to the petitioner’s ineffective assistance
of counsel argument and also declined to certify this issue.
We agree with the district court that the petitioner has failed
to “make a substantial showing of the denial of a constitu-
tional right” (see 28 U.S.C. § 2253(c)(2)) and therefore
decline to expand the COA to consider the merits of this
issue.

   To show ineffective assistance of counsel, Busch must
demonstrate (1) that the defense attorney’s representation
“fell below an objective standard of reasonableness” and (2)
that the attorney’s deficient performance prejudiced the
defendant such that “there is a reasonable probability that, but
for counsel’s unprofessional errors, the result of the proceed-
ing would have been different.” Strickland v. Washington,
466 U.S. 668, 688, 694 (1984). In a guilty-plea case, like the
present case, “in order to satisfy the ‘prejudice’ requirement,
10890                      BUSCH v. WOODFORD
the defendant must show that there is a reasonable probability
that, but for counsel’s errors, he would not have pleaded
guilty and would have insisted on going to trial.” Hill v. Lock-
hart, 474 U.S. 52, 59 (1985).3

   [3] Petitioner’s argument that his trial counsel was deficient
for failing to investigate mental state defenses is a far fetch.
“Trial counsel has a duty to investigate a defendant’s mental
state if there is evidence to suggest that the defendant is
impaired.” Douglas v. Woodford, 316 F.3d 1079, 1085 (9th
Cir. 2003). In the present case, there was no evidence to sug-
gest that the petitioner was impaired. The two pre-trial psychi-
atric evaluations of Busch by Drs. Drury and Rossoff not only
determined that he was competent to stand trial, but also con-
cluded that the petitioner did not suffer from mental disorders.
Busch points to the psychiatric evaluation of Dr. Drury, who
examined Busch prior to trial. (Petitioner’s ER at 1-6.) That
evaluation describes Busch’s prior medical history, including
his suicidal thoughts as a young teenager, his abuse of
methamphetamines and prescription drugs for several years
before the crime and head injuries Busch suffered in an auto
accident in early 1996 and a motorcycle accident in December
1996. (Id. at 4.) After considering this and the other informa-
tion contained in his evaluation, Dr. Drury concluded that
“[b]ased upon personal information, it is my opinion that he
is essentially free of major signs of mental disorder, mental
   3
     The district court, at times in its opinion, does not rely on the correct
standard for demonstrating prejudice in a plea bargain case. See Busch v.
Woodford, No. C 04-4157-MJJ, 2005 WL 1926618, at *6 (N.D. Cal. Aug.
10, 2005). (“Petitioner has not established a reasonable probability that
such information would have led to a different verdict (had the case gone
to trial).”); id. at *7 (“Given this evidence, it is unlikely that a reasonable
jury would have found Petitioner less culpable or returned a verdict less
stringent than first degree murder.”). However, the district court found,
and we agree, that Busch has failed to demonstrate that his trial counsel’s
performance “fell below an objective standard of reasonableness” — the
first prong of the Strickland test — and therefore, this apparent error is
harmless.
                      BUSCH v. WOODFORD                   10891
diseases or psychiatric disease.” (Id. at 6.) In addition, Dr.
Thomson — the expert psychiatrist who testified at the evi-
dentiary hearing on Busch’s state court habeas petition —
agreed that he had no doubt that Busch was competent to
stand trial. (Respondent’s ER at 141.) Although Dr. Thomson
testified that Busch experienced some symptoms of “classical
drug induced paranoia” as a result of his prior substance abuse
(id. at 73) and that he thought Busch may have suffered from
some form of organic brain injury due to his prior head inju-
ries (id. at 135-38, 144-45), he testified that Busch did not
possess any “major” of “full blown” mental illness or mental
disorder (id. at 74-75, 89).

   [4] The petitioner draws a distinction between competency
evaluations and investigating mental defenses, arguing that a
psychiatric evaluation that concludes that an individual is
competent to stand trial is not the same as investigating men-
tal defenses. Although this might be true, the duty to investi-
gate mental defenses is only triggered “if there is evidence to
suggest the defendant is impaired.” Douglas, 316 F.3d at
1085. The defendant fails to point to any credible evidence of
mental incapacity which would have triggered a duty on the
part of his counsel to investigate for possible defenses. More-
over, petitioner’s trial counsel made a reasonable strategic
choice to rely on petitioner’s claims of innocence and decided
not to pursue further investigations into petitioner’s mental
state since he testified that a mental state defense “would have
been inconsistent” with the theory of the case. (Petitioner’s
ER at 167.) See Siripongs v. Calderon, 133 F.3d 732, 734 (9th
Cir. 1998) (holding that “[w]here the attorney has consciously
decided not to conduct further investigation because of rea-
sonable tactical evaluations, the attorney’s performance is not
constitutionally deficient”). Therefore, Busch has failed to
make a substantial showing of the denial of a constitutional
right based on his trial counsel’s performance.

  [5] Busch also fails to show that his trial counsel’s decision
to allow him to make a statement to police detectives on
10892                     BUSCH v. WOODFORD
March 17 fell below an objective standard of reasonableness.
The record supports a finding that the decision was strategic.
As his counsel explained at the evidentiary hearing, without
the statement, there would have been no reason for the prose-
cutor to participate in further plea bargain negotiations. (See
Respondent’s ER at 324.) Moreover, the present case is dis-
tinguishable from Harris ex rel. Ramseyer v. Wood, 64 F.3d
1432, 1436 (9th Cir. 1995), a case relied on by the petitioner,
in which we found the trial counsel’s performance to be defi-
cient in allowing the defendant to give a statement to police.
Importantly, unlike the statement in Harris ex rel. Ramseyer,
here there were certain restrictions placed on the use of
Busch’s statement. Namely, it could not be used in the prose-
cutor’s case-in-chief. (See Petitioner’s ER at 9.) And, perhaps
even more importantly, Busch’s statement was also not
directly incriminating since he did not confess to murdering
the victim; rather, he explained that Donovan Williams killed
the victim.

   [6] Because the ineffective assistance of counsel claims
raised by the petitioner are not “debatable among jurists of
reason,” we decline to expand the COA and, therefore, dis-
miss the petitioner’s uncertified issue for lack of jurisdiction.

II.   Voluntariness of plea

   We now turn to the certified issue. The petitioner argues
that the voluntariness of his plea was undermined by the short
period of time — two hours — that he had to consider the
plea agreement.4 Busch further argues that the limited length
  4
    The total amount of time the petitioner had to consider the plea is in
dispute. The transcript reflects that trial proceedings were suspended for
a little more than two hours before Busch informed the trial court that he
had accepted a plea agreement. However, the respondent argues that the
petitioner had more time than those two hours to consider the plea. His
trial counsel testified that the plea negotiations happened over a couple of
days. Even the petitioner acknowledges that the “proposed disposition was
identical to an offer that Busch had rejected shortly after arraignment fol-
lowing his arrest.” (Petitioner’s Opening Br. at 12.)
                         BUSCH v. WOODFORD                        10893
of time, in combination with his mental defects, rendered his
plea involuntary.

   [7] The test for determining whether a plea is valid is
“whether the plea represents a voluntary and intelligent choice
among the alternative courses of action open to the defen-
dant.” Hill, 474 U.S. at 56 (quoting Alford, 400 U.S. at 31)
(quotation marks omitted); Boykin v. Alabama, 395 U.S. 238,
242-43 (1969). “[T]he record must affirmatively disclose that
a defendant who pleaded guilty entered his plea understand-
ingly and voluntarily.” Brady v. United States, 397 U.S. 642,
747 n.4 (1970). A guilty plea is coerced where a defendant is
“induced by promises or threats which deprive [the plea] of
the nature of a voluntary act.” Iaea v. Sunn, 800 F.2d 861, 866
(9th Cir. 1986) (quotation marks and citation omitted). To
determine the voluntariness of the plea, we look to the totality
of the circumstances, examining both the defendant’s “subjec-
tive state of mind” and the “constitutional acceptability of the
external forces inducing the guilty plea.” Id.

   [8] The district court issued a certificate of appealability on
this issue noting that it was a novel argument and indicating
that there was no case law on the question. Busch v. Wood-
ford, No. C 04-4157-MJJ, slip op. at 3 (N.D. Cal. Mar. 24,
2006.) Indeed, the case law on this issue is quite limited.5
However, the amount of time Busch had to consider the plea
is only relevant if it somehow rendered his plea coerced, and
therefore involuntary. Recall that the jury had already been
empaneled and that the court had delayed opening arguments
until the following morning in order to provide Busch’s coun-
sel and the prosecution an opportunity to reconsider a plea
bargain. Therefore, there was a plausible reason for the argu-
ably short two hours Busch had to consider the proposed plea
agreement. With this in mind, the proper question for review
  5
   This court has held that nine days to consider a plea bargain was not
inadequate. United States v. Estrada-Plata, 57 F.3d 757, 760-61 (9th Cir.
1995).
10894                BUSCH v. WOODFORD
is whether the California Supreme Court “clearly erred in its
application of controlling federal law” in determining that the
petitioner’s plea was voluntary. See Delgado II, 223 F.3d at
982. We conclude that it did not.

   In accepting Busch’s plea, the state trial court conducted a
thorough plea colloquy. As the district court noted, the tran-
script of the plea colloquy covers sixteen pages. As is evi-
denced from the following exchange, the state trial court
specifically addressed the adequacy of the length of time the
defendant had to discuss the plea agreement with his counsel.

    The Court:      Now, have you talked about this case
                    with your lawyers?

    [Petitioner]:   Yes.

    The Court:      And you believe you’ve had enough
                    time to talk with them about your
                    case?

    [Petitioner]:   I guess.

    The Court:      Well, is that a yes or a no?

    [Counsel]:      Maybe you could ask the next ques-
                    tion first and maybe then he’ll be
                    able to answer this question.

    The Court:      Have you told your attorneys all the
                    facts and circumstances that are
                    known to you about your case?

    [Petitioner]:   Yes.

    The Court:      You’ve had enough time to talk with
                    them about your case?
                          BUSCH v. WOODFORD                          10895
      [Petitioner]:     Yeah.

      The Court:        Is that a yes? I just need to be sure.

      [Petitioner]:     Yes.

      The Court:        Okay. Are you pleading guilty freely
                        and voluntarily?

      [Petitioner]:     Yes.

(Respondent’s ER at 30.) Based in part on this exchange, the
trial court found that the petitioner “understands the conse-
quences to him of his plea of guilty. His plea of guilty is
freely and voluntarily given, and there’s a factual basis for his
plea of guilty.” (Id. at 36.)

   [9] In Blackledge v. Allison, 431 U.S. 63 (1977), the
Supreme Court held that findings made by the judge accept-
ing the plea “constitute a formidable barrier in any subsequent
collateral proceedings. Solemn declarations in open court
carry a strong presumption of verity.” Id. at 74; cf. Chizen v.
Hunter, 809 F.2d 560, 562 (9th Cir. 1986) (holding that the
defendant overcame statements made at his plea colloquy and
showed his plea was involuntary where the plea was induced
by misrepresentations by the defendant’s counsel as to what
the defendant’s sentence would in fact be under the plea
agreement). In a case where the defendant decided to plead
guilty after trial had begun, the Tenth Circuit rejected the
defendant’s claim that the limitations on time for him to con-
sider a plea bargain rendered it involuntary, relying in part on
the defendant’s “participat[ion] in a [plea] colloquy that
leaves little doubt that his plea was knowing and voluntary.”
United States v. Graham, 466 F.3d 1234, 1239 (10th Cir. 2006).6
  6
   Although Graham involved a direct appeal from a plea to a federal
offense and the plea was taken pursuant to Federal Rule of Criminal Pro-
cedure 11, the plea colloquy demonstrated voluntariness under the same
constitutional standard applicable in this case. See Alford, 400 U.S. at 31;
Brady, 397 U.S. at 784.
10896                BUSCH v. WOODFORD
   The petitioner contends that the court should have ques-
tioned the voluntariness of his plea in light of Busch’s “I
guess” response, instead of “shoehorn[ing] Busch’s answer in
a way that masked his grave doubts about whether to plead.”
(Petitioner’s Opening Br. at 13.) The trial court, however, did
respond to Busch’s “I guess” answer. The court again asked
if he had enough time to talk to his attorneys about the plea.
(Respondent’s ER at 30.) When Busch responded “Yeah,” the
court asked Busch to clarify, “Is that a yes?” Id. Moreover,
earlier in the exchange when Busch did not understand a
question, he had clearly answered “No.” (See id. at 27.)

   [10] Busch argues that the limited time he had to consider
the plea agreement must be considered in light of his “mental
state.” The petitioner relies on the testimony of Dr. Thomson
offered at the evidentiary hearing. Dr. Thomson testified to
certain “factors,” namely immaturity, history of brain head-
injury accidents, history of methamphetamine use and limited
education, which impacted the defendant’s mental state at the
time he considered the plea agreement. (Petitioner’s ER at
75.) When pressed, however, Dr. Thomson admitted that there
was no evidence to support a “major mental illness diagno-
sis.” (Id. at 80-81.) Moreover, Dr. Drury, who provided a
competency evaluation prior to trial, found Busch to be “es-
sentially free of major signs of mental disorder, mental dis-
ease or psychiatric disease” and concluded that he was
competent to stand trial. (Id. at 6.) The competency standard
to plead guilty is the same as that to stand trial. Miles v.
Stainer, 108 F.3d 1109, 1112 (9th Cir. 1997) (citing Godinez
v. Moran, 509 U.S. 389, 402 (1993)). Any evidence of mental
deficiencies did not undermine the voluntariness of Busch’s
plea even in light of the alleged limitation to two hours he
claims he had to consider the proposed plea agreement.

   [11] Busch’s testimony at the evidentiary hearing describes
the difficulty he had in making the decision to plead guilty.
(Respondent’s ER at 136-41.) Recall, however, that Busch
was offered identical terms shortly after he was arrested, more
                     BUSCH v. WOODFORD                   10897
than a year before he pleaded guilty. We have no doubt that
the decision to plead guilty is a difficult one for many defen-
dants, but the fact that one struggles with the decision, and
might later even come to regret it, does not render it coerced.
See United States v. Johnson, 539 F.2d 1241, 1243 (9th Cir.
1976). Here, Busch participated in a thorough plea colloquy,
in which he answered in the affirmative that his plea was vol-
untary under the circumstances and, specifically answered in
the affirmative when asked if he had had enough time to dis-
cuss the plea with his attorneys. We conclude that the Califor-
nia Supreme Court did not “clearly err in its application of
controlling federal law” by determining that Busch’s plea was
voluntary. Delgado II, 223 F.3d at 982.

  AFFIRMED.
