PREGERSON, Circuit Judge:
Maxwell Hoffman (“Hoffman”) appeals the district court’s dismissal of his petition for a writ of habeas corpus, in which he claims, inter alia, that the district court erred in finding that: (1) Idaho Code § 19-2719 was an adequate and independent state law ground to support the state court’s judgment that petitioner had defaulted his ineffective assistance of counsel claims; (2) petitioner’s due process rights were not violated by the state trial court’s refusal to allow petitioner’s attorney to be present at the presentence interview conducted by the state probation officer; (3) the “heinous, atrocious and cruel” aggravating factor in Idaho’s capital sentencing law, Idaho Code § 19 — 2515(h)(5), was not unconstitutionally vague; and (4) the application of Idaho’s capital sentencing scheme did not unconstitutionally deprive petition[527]*527er of the right to have a jury determine the presence of an aggravating circumstance in light of Apprendi v. New Jersey, 530 U.S. 466, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000).
This court has jurisdiction to review petitioner’s claims under 28 U.S.C. §§ 1291 and 2254. We affirm the district court’s ruling that Hoffman’s ineffective assistance of counsel claims were procedurally defaulted under Idaho Code § 19-2719, but reverse on the question whether the Idaho statute is “adequate” to preclude federal review of the underlying constitutional claim. Hoffman v. Arave, 973 F.Supp. 1152, 1166-68 (D.Idaho 1997). We also reverse the district court’s finding that Hoffman’s Sixth Amendment right to counsel was not violated by the Idaho trial court’s refusal to allow petitioner’s attorney to be present at the presentence interview conducted by a state probation official. Hoffman v. Arave, 73 F.Supp.2d 1192, 1203-07 (D.Idaho 1998).1 With respect to petitioner’s remaining claims, we uphold the findings of the district court.2 Accordingly, we affirm in part, reverse in part, and remand for an evidentiary hearing on petitioner’s ineffective assistance of counsel claims.
I.
Facts and Procedural History
On March 16, 1989, an Idaho jury found Hoffman guilty of first degree murder for killing Denise Williams, a police informant. At trial, Hoffman, who is indigent, was represented by county public defenders William Wellman (“Wellman”) and Charles Coulter (“Coulter”). Following Hoffman’s conviction, the state sought the death penalty. Pursuant to Idaho law, the state trial court conducted a separate sentencing proceeding, which included a presentence interview of the defendant by a probation officer, the submission of a presentence report written by the probation officer, and a sentencing hearing held by the court in which aggravating and mitigating evidence was presented by the state and defense counsel. After considering the testimony at trial and sentencing, and the presentence report submitted by the probation officer, the trial court imposed the death penalty.
Before sentencing proceedings began, Hoffman’s trial counsel filed a motion requesting the right to have counsel present at the presentence interview with the probation officer, which the court denied. Trial counsel also filed a motion pursuant to Idaho Code §§ 19-2522(3)(a-f) and (5) requesting that the court order a psychiatrist or psychologist to examine “the mental condition of the defendant” and submit a written report to defense counsel. The court granted the motion and appointed psychologist David Sanford, Ph.D., to prepare a written evaluation of Hoffman and submit it to defense counsel.3 Dr. Sanford prepared a report, in which he concluded that Hoffman was “illiterate,” and “shows a rather consistent picture of brain damage to the left hemisphere” that created [528]*528“significant articulation problems” and an “overall borderline intellectual capability.” Hoffman’s attorneys elected not to present Sanford’s report at sentencing or “make any use of the psychological findings.”4 State v. Hoffman, 123 Idaho 638, 861 P.2d 934, 937 (1993), cert. denied, Hoffman v. Idaho, 511 U.S. 1012, 114 S.Ct. 1387, 128 L.Ed.2d 61 (1994).
On June 9, 1989, the court held a sentencing hearing to determine whether Hoffman would receive life in prison or the death penalty. Hoffman testified that he had spent most of his childhood as a ward of the state and some of his adult life in state penal institutions where he was incarcerated for burglary and robbery. He testified' that his schooling had been sporadic, that he had never learned to read, and that he had chronic problems with alcohol and drugs.
On June 13, 1989, the trial court, after finding that the aggravating factors outweighed the mitigating evidence, -sentenced Hoffman to death. In a written decision, the court found that two statutory aggravating factors, the killing of a government witness and the particularly “heinous, atrocious and cruel” nature of the murder, outweighed the mitigating factors, which included Hoffman’s drug addiction, educational deficiencies, and disadvantaged social background.
Hoffman’s petition for state post-conviction relief was timely filed on July 25, 1989, by trial counsel Wellman and Coulter, who continued to provide legal representation. Counsel requested .an additional psychological evaluation, which was denied. The state court held an eviden-tiary hearing on the petition, which alleged multiple claims of error at trial and sentencing, and denied relief on December 13, 1989.
Wellman and Coulter appealed to the Idaho Supreme Court. The appeal consolidated the direct appeal and post-conviction claims of error as required by Idaho Code § 19-2719. No issues regarding ineffective assistance of counsel were raised in the appeal. On January 29, 1993, the Idaho Supreme Court affirmed Hoffman’s death sentence and the state trial court’s denial of his post-conviction petition. See Hoffman, 851 P.2d at 944, cert. denied, Hoffman v. Idaho, 511 U.S. 1012, 114 S.Ct. 1387, 128 L.Ed.2d 61 (1994).
Hoffman, represented by newly appointed counsel, Charles Peterson (“Peterson”) and Ellison Matthews (“Matthews”), filed a second petition for post-conviction relief in the state district court on July 7, 1995. The petition alleged fourteen grounds for relief, including three claims asserting that petitioner had been denied the effective assistance of counsel at trial, sentencing, and on direct appeal. The state moved to dismiss the petition, asserting that the fourteen claims were procedurally defaulted because Idaho Code § 19-2719 mandates the filing of all post-conviction claims within forty-two days of the entry of judgment. The state district court denied relief on May 20,1996.
Hoffman’s attorneys appealed the dismissal of the second petition to the Idaho Supreme Court. The state filed a motion to dismiss, in which it renewed its argument that the claims were procedurally defaulted. On December 6, 1996, the Idaho Supreme Court issued a brief, unexplained ruling granting the state’s motion. See Hoffman, 973 F.Supp. at 1164.
On April 2, 1996, Hoffman’s counsel filed a federal habeas petition in the United States District Court for the District of Idaho asserting, inter alia, that: Idaho Code § 19-2719 deprived petitioner of his [529]*529constitutional right to due process and equal protection; counsel’s performance at trial, sentencing, and on appeal was deficient and prejudicial in violation of petitioner’s Sixth Amendments rights; petitioner’s ineffective assistance of counsel claims were not proeedurally barred; the trial court’s refusal to allow petitioner to have counsel present for the presentenee interview conducted by the probation officer violated his Fifth, Sixth, Eighth, and Fourteenth Amendment rights; and the “heinous, atrocious and cruel” aggravating factor listed under Idaho Code § 19-2515(h)(5) was unconstitutionally vague. See Hoffman, 973 F.Supp. at 1152.
The District Court of Idaho issued two opinions concerning Hoffman’s habeas petition. In the first opinion, issued on June 13, 1997, the court dismissed with prejudice some of Hoffman’s claims for relief, including his ineffective assistance of counsel claims, based upon a finding of procedural default.5
On December 28, 1998, the district court issued its second opinion concerning Hoffman’s habeas petition, which addressed the merits of the remaining claims.6 See id. The court rejected all of the surviving claims in the petition. See id. On January 20, 1999, Hoffman’s counsel filed a notice of appeal of the district court’s denial of the petition.
The district court’s decision to grant or deny a § 2254 habeas petition is reviewed de novo. Bribiesca v. Galaza, 215 F.3d 1015, 1018 (9th Cir.2000). Dismissal based on state procedural default presents issues of law reviewed de novo. Fields v. Calderon, 125 F.3d 757, 759-60 (9th Cir.1997).
II.
Ineffective Assistance of Counsel Claims
The right to the effective assistance of counsel is “fundamental and essential to fair trials.” Gideon v. Wainwright, 372 U.S. 335, 344, 83 S.Ct. 792, 9 L.Ed.2d 799 (1963); see also Evitts v. Lucey, 469 U.S. 387, 394-96, 105 S.Ct. 830, 83 L.Ed.2d 821 (1985). Because this right “lies at the very foundation of the adversary system of criminal justice,” habeas courts must be “particularly vigilant in scrutinizing the adequacy of state rules of procedural default which have the effect of barring federal habeas review of claims of ineffective [530]*530assistance of counsel.” English v. Cody, 146 F.3d 1257, 1259 (10th Cir.1998).7
In this petition, Hoffman renews claims that he was deprived of his constitutional right to the effective assistance of counsel at trial, sentencing, and on appeal. The district court held that Idaho Code § 19-2719 constituted a procedural bar that precluded federal habeas review of Hoffman’s ineffective assistance of counsel claims. While we agree with the district court that Hoffman’s ineffective assistance of counsel claims are procedurally defaulted under Idaho Code § 19-2719, we find that the statute is an unreasonable restriction on the exercise of the federally protected constitutional right to counsel and therefore is inadequate to bar federal review. Michel v. Lousiana, 350 U.S. 91, 93-94, 76 S.Ct. 158, 100 L.Ed. 83 (1955); English, 146 F.3d at 1260-64.
A. Procedural Default
Idaho Code § 19-2719 requires capital defendants to “file any legal or factual challenge to the sentence or conviction that is known or reasonably should be known”8 within forty-two days of the entry of judgment.9 The judgment against Hoffman was entered on June 13, 1989. Hoffman’s ineffective assistance of counsel claims were raised for the first time in a second petition for post-conviction relief, which was filed on July 7, 1995. The state responded with a motion to dismiss, arguing that the claims in Hoffman’s post-conviction petition were procedurally defaulted because they were not timely filed within the forty-two day period required by the statute. In a two-sentence order, the Idaho Supreme Court granted the state’s motion and dismissed the petition. See Hoffman, 973 F.Supp. at 1164. The federal district court concluded that Hoffman’s ineffective assistance of counsel claims, raised for the first time after the expiration of the statute’s forty-two day deadline, were procedurally defaulted. Id. at 1165-66; see also Ylst v. Nunnemaker, 501 U.S. 797, 802, 111 S.Ct. 2590, 115 L.Ed.2d 706 (1991); Coleman v. Thompson, 501 U.S. 722, 735-36, 111 S.Ct. 2546, 115 L.Ed.2d 640 (1991). We agree with the district court that Hoffman’s ineffective assistance of counsel claims are procedurally defaulted under Idaho Code § 19-2719, but now address the question whether this procedural default is adequate to preclude federal review.
B. The Adequate and Independent State Law Grounds Doctrine
In the usual case, state procedural rules dictate the time and manner in which federal constitutional rights are adjudicated in state court. Comity and federalism require federal courts to defer to the states’ “dignitary interest in seeing that their state law decisions are not ignored by a federal habeas court.” Coleman, 501 U.S. at 738, 111 S.Ct. 2546. When a state court litigant raises a federal claim in a manner that does not comply with a state procedural rule, the state court may dismiss that claim as defaulted. So long as the dismissal relies on a state law ground that is independent of the federal question and adequate to support the judgment, it will be insulated from federal review. See, [531]*531e.g., Wainwright v. Sykes, 433 U.S. 72, 81, 97 S.Ct. 2497, 53 L.Ed.2d 594 (1977).
The Supreme Court has held, however, that if a state procedural rule frustrates the exercise of a federal right, that rule is “inadequate” to preclude federal courts from reviewing the merits of the federal claim. See, e.g., Staub v. City of Baxley, 355 U.S. 313, 325, 78 S.Ct. 277, 2 L.Ed.2d 302 (1958) (holding that denial of petitioner’s constitutional plaims for failure to attack specific sections of the challenged ordinance was an inadequate state law ground).
The “inadequate” state grounds doctrine is rooted in a concern that a state’s rigid adherence to technical requirements of dubious validity may result in fundamental unfairness where federal rights are at stake. See Davis v. Wechsler, 263 U.S. 22, 23, 44 S.Ct. 13, 68 L.Ed. 143 (1923) (holding that “the assertion of Federal rights, when plainly and reasonably made, is not to be defeated under the name of local practice”). In a criminal case, the test for whether a state procedural rule constitutes an “insuperable barrier” to the assertion of a federal right is “whether the defendant has had ‘a reasonable opportunity to have the issue as to the claimed right heard and determined’ by the State court.” Michel, 350 U.S. at 93, 76 S.Ct. 158 (internal citations omitted).
In Reece v. Georgia, a capital case, the Supreme Court applied the Michel test to a state court’s dismissal of petitioner’s challenge to the composition of the grand jury, filed after an indictment was returned. The Georgia Supreme Court refused to consider Reece’s claim on the merits, holding that Reece’s claim was untimely under a state procedural rule requiring defendants to raise grand jury composition challenges before the indictment was returned. See Reece v. Georgia, 350 U.S. 85, 89, 76 S.Ct. 167, 100 L.Ed. 77 (1955). The Supreme Court reversed. Noting that Reece had no access to counsel during the preindictment stage of the proceedings and that the grand jury was convened by an order that failed to give him notice that a case was being brought against him, the Court concluded that the state court’s finding of procedural default was “utterly unrealistic.” Id. The Supreme Court’s interpretation of the Michel test in Reece makes clear that where the application of a state procedural rule operates to frustrate the exercise of a federal constitutional right, federal courts may reach the merits of the underlying federal claim.
C. Idaho Code § 19-2719 Frustrated the Exercise of Hoffman’s Sixth Amendment Claims
The unique difficulties involved in arguing claims of ineffective assistance of counsel have led federal habeas courts to find “inadequate” a state procedural bar that denies a petitioner “any meaningful review of his ineffective assistance claim.” Brecheen v. Reynolds, 41 F.3d 1343, 1364 (10th Cir.1994). Indeed, three federal circuit courts have held that where a criminal defendant does not comply with the procedural requirement that his ineffective assistance of counsel claims be raised on direct appeal, he has not, in most circumstances, waived his right to have a federal court review those claims on the merits.
In English v. Cody, the Tenth Circuit held that a criminal defendant must be able to obtain an objective assessment of trial counsel’s performance and be allowed to develop adequately the factual basis of any ineffective assistance of counsel claim. Considering an Oklahoma statute requiring criminal defendants to raise all ineffective assistance of counsel claims on direct review, the court concluded that the state law would not bar federal review on the grounds of procedural default unless: (1) the defendant was appointed separate counsel on appeal; and (2) the claim could be resolved on the basis of the trial record alone. The opinion noted that, unless one of the narrow exceptions applied, there is a “constitutional imperative that this court [532]*532disregard a state procedural bar for the review of ineffective assistance [of counsel] claims.” English, 146 F.3d at 1261. The Second and Seventh Circuits have reached the same conclusion. See Guinan v. United States, 6 F.3d 468, 471-73 (7th Cir.1993) (holding that ineffective assistance of counsel claims not raised on direct appeal were not waived if the defendant continued to be represented by trial counsel or if the ineffectiveness claims required investigation outside of the trial record); Ciak v. United States, 59 F.3d 296, 303-04 (2d Cir.1995) (same).
Because Idaho’s unitary statute requires the consolidation of post-conviction and direct appeal claims in a single petition and requires such consolidated claims to be filed within forty-two days of entry of judgment, it requires ineffective assistance of counsel claims to be raised on direct appeal. Thus, Hoffman is similarly situated to the defendants in Cody, Guinan, and Ciak with respect to the constraints imposed by state procedural rules on the timeliness of his ineffective assistance of counsel claims.
In 1984, the Idaho Legislature enacted Idaho Code § 19-2719 “to accomplish the purpose of eliminating unnecessary delay in carrying out a valid death sentence.”10 The statute requires a capital defendant, within forty-two days of the entry of the judgment imposing the death penalty, to “file any legal or factual challenge to the sentence or conviction that is known or reasonably should be known.” 11 This for[533]*533ty-two day deadline is the shortest in the nation and applies to “[a]ny remedy available by post-conviction procedure, habeas corpus or any other provision of state law.” 12 Failure to file a claim for post-conviction relief within the statutory time limit is deemed a waiver, and the Idaho courts are stripped of the jurisdiction to hear “any such claims for relief.”13 In addition, § 19-2719 requires capital defendants to present simultaneously all post-conviction and direct appeal claims by combining them in a single petition for review by the Idaho Supreme Court.14
The Idaho Supreme Court has strictly construed the waiver provision of the statute as limiting a capital defendant to “one opportunity to raise all challenges to the conviction and sentence in a petition for post-conviction relief’ except in “unusual cases.” Rhoades, 820 P.2d at 677, cert. denied, 504 U.S. 987, 112 S.Ct. 2970, 119 L.Ed.2d 590 (1992). Allegations of ineffective assistance of counsel are not considered claims that fall within the “unusual eases” exception, but instead are considered claims that “should reasonably be known immediately upon the completion of trial.” Pizzuto v. State, 127 Idaho 469, 903 P.2d 58, 61 (1995); see also Paz v. State, 123 Idaho 758, 852 P.2d 1355, 1356-57 (1993). This is true even if the capital defendant seeking review of his ineffective assistance of counsel claims is also represented by trial counsel during post-conviction proceedings. See Paz, 852 P.2d at 1357-58 & n. 3 (Bistline, J., dissenting).
Applying Idaho’s forty-two day filing-deadline to Hoffman’s ineffective assistance of counsel claims raises fairness concerns similar to those posed by applying Georgia’s statute of limitations to Reece’s grand jury composition challenge. In Hoffman’s case, the Idaho Supreme Court held that petitioner’s ineffective assistance of counsel claims were procedurally barred because they were filed after the expiration of the state’s forty-two day statutory deadline. The Idaho Supreme Court applied the rule despite the fact that Hoff[534]*534man continued to be represented by his original trial counsel during the forty-two day period.15 See also English, 146 F.3d at 1260 (observing that ineffective assistance of counsel claims involve assertions of attorney incompetence that require a petitioner “to consult with different counsel on appeal in order to obtain an objective assessment of trial counsel’s performance”).
Significantly, both the Idaho Supreme Court and the Idaho legislature have since adopted new regulations designed to prevent this situation from recurring. In 1995, the Idaho Supreme Court promulgated Idaho Criminal Rule 44.2, which requires the trial court in a capital case to appoint at least one attorney other than trial counsel to represent the defendant in post-conviction proceedings. In the same year, the Idaho legislature enacted Idaho Code § 19-2719A, which permits the trial court to advise capital defendants that they are entitled to new counsel to pursue ineffective assistance of counsel claims at post-conviction proceedings.16
Idaho’s forty-two day filing deadline, as applied to Hoffman, is uniquely harsh. Most states permit defendants to file petitions for post-conviction relief following the completion of their direct appeals.17 This bifurcated system allows for the appointment of new counsel, who can evaluate the record objectively to determine whether there are meritorious claims of ineffective assistance at trial and sentencing.
In Hoffman’s case, the application of § 19-2719, which at that time did not provide for the appointment of independent counsel, permitted trial counsel to continue to represent him during post-conviction proceedings, which they did. As a result, Hoffman was deprived of counsel who could review the record objectively for ineffective assistance of counsel claims. Not surprisingly, Hoffman’s trial counsel failed to raise and argue the issue of their own ineffectiveness in post-conviction proceedings. The practical reality, recognized by other states that employ the unitary post-conviction and appellate procedures18— and, ultimately, recognized by the state of Idaho itself19 — -is that “[i]t is the rare attorney who can be expected to contend on appeal that his representation was so poor that he deprived his client of a fair trial.” Ciak, 59 F.3d at 303.
No allegation of ineffective assistance of counsel was made on Hoffman’s behalf until 1995, when a successive petition for [535]*535post-conviction relief was filed by appointed counsel Peterson and Matthews, who replaced Hoffman’s trial counsel. Peterson and Matthews investigated errors apparent from the record, and supplied the court with depositions and affidavits in which Hoffman’s trial counsel admitted that they failed to: (1) obtain or review their client’s educational, medical, or psychological records; (2) request a psychiatric evaluation of their client until after the trial despite awareness of his illiteracy, low intelligence, and psychological problems; and (3) follow up on the conclusion, stated in Dr. Sanford’s report, that Hoffman suffered from possible brain damage.
Peterson and Matthews also investigated errors outside of the record, and supplied the court with depositions and affidavits in which trial counsel, neither of whom had previously tried a capital case, admitted that they had advised Hoffman to reject a plea of life in prison because they mistakenly believed, based on their misinterpretation of existing case law, that the Idaho death penalty statute would be found unconstitutional. Peterson and Matthews’s petition was the first time that allegations documenting specific instances in which Hoffman’s counsel had been ineffective had been presented to the state court.
As Peterson and Matthews’s investigation shows, a claim of ineffective assistance of counsel requires review of the trial transcript and the entire record to determine the nature, frequency, and effect of counsel’s errors. But Idaho Code § 19-2719 makes no provision for expedited delivery of trial transcripts to ensure that compliance with the forty-two day filing deadline does not deprive capital defendants of access to the complete record of their cases.20 Indeed, the record indicates that Hoffman’s trial counsel prepared their post-conviction petition for relief without access to the trial transcript, which was completed on November 6, 1989, more than three months after the post-conviction petition was filed. Completion and service of the full record did not occur until late March of 1990, several months after the state court ruled to deny Hoffman’s post-conviction petition.
The investigation conducted by Peterson and Matthews also shows that raising a claim of ineffective assistance of counsel requires that new counsel have the opportunity to conduct an investigation beyond the court records to uncover possible omissions made by trial counsel in the investigation and presentation of the case. See, e.g., Osborn v. Shillinger, 861 F.2d 612, 623 (10th Cir.1988) (“[Ijneffectiveness claims are ordinarily inappropriate to raise on direct appeal because they ... cannot be made on the basis of the record[.]”); Cruz v. Warden, 907 F.2d 665, 670 (7th Cir.1990) (“An ineffective assistance claim alleging that counsel failed to prepare involves facts outside the trial record and presents a situation in which the Illinois courts will not invoke the res judicata or waiver doctrines.”).
Hoffman’s case involves allegations of ineffectiveness at trial, sentencing, and on appeal, stemming from counsel’s legally inaccurate advice regarding the possibility that the death penalty would be imposed and counsel’s failure to review educational, physical, and psychiatric records in order to present mitigating evidence. All of these allegations required investigation outside of the record at trial.
For the reasons outlined above, § 19-2719 effectively prevented Hoffman from [536]*536timely raising his ineffective assistance of counsel claims.
D. Evidentiary Hearing on Ineffective Assistance of Counsel Claims
Because the state court denied Hoffman’s ineffective assistance of counsel claims without holding a hearing, and the Idaho Supreme Court and the federal district court affirmed the denial on procedural grounds, those claims have never been litigated on the merits. Without the benefit of an evidentiary hearing, it is impossible to evaluate the strength of Hoffman’s defense at trial and sentencing. Therefore, we cannot conclude as a matter of law that there is no reasonable possibility that offering expert testimony and a thorough history of Hoffman’s educational, medical, and psychological problems at the time of the murder might have reduced the likelihood that the death penalty would have been imposed. We therefore remand for an evidentiary hearing to develop a factual record regarding Hoffman’s ineffective assistance of counsel claims. See Siripongs v. Calderon, 35 F.3d 1308, 1315-16 (9th Cir.1994); Smith v. McCormick, 914 F.2d 1153, 1170 (9th Cir.1990).
III.
Petitioner’s Fifth and Sixth Amendment Rights During The Presentence Interview
Hoffman challenges the trial court’s denial of his request to have counsel present during the presentence interview with the probation officer as a violation of his Fifth, Sixth, and Fourteenth Amendment rights. Hoffman contends that under Estelle v. Smith, 451 U.S. 454, 101 S.Ct. 1866, 68 L.Ed.2d 359 (1981), the court may not, during the capital sentencing hearing, and when making the sentence determination, rely upon statements obtained through the custodial presentence interview without the aid of counsel. Although petitioner failed to raise this claim in his consolidated appeal to the Idaho Supreme Court, the Idaho death penalty statute requires mandatory review of the entire record for sentencing errors. See Beam v. Paskett, 3 F.3d 1301, 1306-07 (9th Cir.1993), overruled on other grounds by Lambright v. Stewart, 191 F.3d 1181, 1185 (9th Cir.1999). All sentencing errors are treated as implicitly raised, removing the bar of procedural default. See Beam, 3 F.3d at 1306-07. The federal district court thus appropriately reached the merits of Hoffman’s Fifth and Sixth Amendment Estelle claims. See Hoffman, 73 F.Supp.2d at 1203-07. The district court denied the claims by distinguishing Hoffman’s case from Estelle, and held that the presentence interview is not a critical stage. See id. at 1207. Because we conclude that Estelle controls in the context of a capital case, we reverse.
In all capital cases, Idaho law requires a presentence investigation and report prior to the commencement of the sentencing hearing. See Idaho Code § 19-2515(c); State v. Creech, 105 Idaho 362, 670 P.2d 463 (1983). The presentence report provides “crucial information” to the court, Idaho v. Romero, 116 Idaho 391, 396, 775 P.2d 1233 (1989), including information about the defendant’s social history, educational background, “sense of values and outlook on life,” and the “presentence investigator’s analysis.” I.C.R. 32. The trial court denied Hoffman’s motion for counsel at the presentence interview, and the probation officer refused Hoffman’s renewed requests for counsel during the interview itself. The trial court instructed the Deputy Attorney General to ensure that Hoffman was advised by the probation officer at the beginning of his presen-tence interview of his right to remain silent. See Hoffman, 73 F.Supp.2d. at 1206.
During the interview, Hoffman made a number of incriminating statements. He discussed the murder of Denise Williams with the probation officer and made multiple equivocal statements about his involve[537]*537ment.21 Hoffman conceded in the interview that he had known that Williams was an informant and that he did not think that what she did was right. Hoffman also told the probation officer that although he had recently found the “Lord,” he had been previously living the life of a “demon.” Most significantly, Hoffman admitted that he had been present at two unrelated murders and indicated that although he could have helped prevent these murders, he did not make any such attempt. The probation officer recommended in the presentence report to the trial court that Hoffman be sentenced to the “maximum punishment,” which in this case was death.
Idaho contends that applying Estelle to Hoffman’s case would constitute a new rule in violation of Teague v. Lane, 489 U.S. 288, 109 S.Ct. 1060, 103 L.Ed.2d 334 (1989). Once the state raises the Teague defense, we are compelled to address whether Teague applies before determining the merits of the claim. See Caspari v. Bohlen, 510 U.S. 383, 389, 114 S.Ct. 948, 127 L.Ed.2d 236 (1994). With few exceptions, the Teague non-retroactivity doctrine prohibits courts from announcing new rules of law in federal habeas proceedings.22 See, e.g., Reynoldsville Casket Co. v. Hyde, 514 U.S. 749, 758, 115 S.Ct. 1745, 131 L.Ed.2d 820 (1995). A decision announces a “new rule” if it “breaks new ground or imposes a new obligation.” Teague, 489 U.S. at 301, 109 S.Ct. 1060. “To determine what counts as a new rule, Teague requires courts to ask whether the rule a habeas petitioner seeks can be meaningfully distinguished from that established by binding precedent at the time his state court conviction became final.” Wright v. West, 505 U.S. 277, 304, 112 S.Ct. 2482, 120 L.Ed.2d 225 (1992) (O’Connor, J., concurring). We consider the “legal landscape as it [ ] existed” on March 28,1994, the date Hoffman’s conviction and sentence became final.23 Caspari, 510 U.S. at 390, 114 S.Ct. 948 (internal quotations omitted).
A. Hoffman’s Fifth Amendment Claim
The Supreme Court decided Estelle v. Smith in 1981, over a decade before Hoffman’s conviction became final. In Estelle, a Texas trial court sua sponte ordered the state’s attorney to arrange a psychiatric evaluation of the defendant to determine the defendant’s competency to stand trial. See Estelle, 451 U.S. at 456-57, 101 S.Ct. 1866. The defendant was found competent, and, after a jury trial, convicted of murder. See id. at 457, 101 S.Ct. 1866. As required by Texas law, a separate proceeding was then undertaken before the same jury to consider whether the defendant should receive the death penalty. See id. at 458, 101 S.Ct. 1866. During the sentencing hearing, the state offered the testimony of the court-appointed psychiatrist, who had interviewed the defendant solely for competency purposes, to establish the defendant’s future dangerousness. The psychiatrist testified before the jury that the defendant “is a very severe sociopath,” that “he will continue his previous behavior,” that his condition will “only get worse,” and that he “has no remorse or sorrow for what he has done.” [538]*538Id. at 459-60, 101 S.Ct. 1866. After hearing the psychiatrist’s testimony, the jury imposed the death penalty. See id.
The Supreme Court in Estelle concluded that the Fifth Amendment applied to the defendant’s interview with the psychiatrist, when the incriminating statements made by the defendant formed the basis of the psychiatrist’s testimony, which was considered by the jury in determining the sentence to be imposed on the defendant. Id. at 462-69, 101 S.Ct. 1866. The Supreme Court began its Fifth Amendment analysis by noting that “the availability of the ... [Fifth Amendment] privilege does not turn upon the type of proceeding in which its protection is invoked, but upon the nature of the statement or admission and the exposure which it invites.” Id. at 462, 101 S.Ct. 1866 (citations omitted). The Supreme Court then found that the consequence at stake in capital sentencing, the “ultimate penalty of death,” triggered the constitutional protection of the Fifth Amendment. Id. at 462-63, 101 S.Ct. 1866. “Just as the Fifth Amendment prevents a criminal defendant from being made ‘the deluded instrument of his own conviction,’ it protects him as well from being made the ‘deluded instrument’ of his own execution.” Id. at 462, 101 S.Ct. 1866 (internal citations omitted).
One year later, this court concluded that under Estelle, the Fifth Amendment applied to inculpatory statements made during a presentence interview with a probation officer. See Jones v. Cardwell, 686 F.2d 754, 756 (9th Cir.1982) (“The reasoning that underlies the decision in Estelle supports application of the Fifth Amendment privilege to the sentencing procedures in the instant case.”). We reasoned that although not
every encounter between the state and a convicted but unsentenced defendant •brings the Fifth Amendment privilege into play.... [W]here, as here, the state’s agent seeks from the convicted defendant a confession of additional criminal activity and that confession is used to enhance a defendant’s sentence, we think it beyond peradventure that the defendant may properly claim the protection of the privilege against self-incrimination.
Id.
Hoffman’s claim that his Fifth Amendment privilege applied during the presen-tence interview is controlled by the Supreme Court’s ruling in Estelle that a capital defendant’s inculpatory statements made during an interview with a psychiatrist are protected by the Fifth Amendment privilege, and this court’s ruling in Jones that a defendant’s inculpatory statements made during a presentence interview are protected by the Fifth Amendment when the statements may be used to increase the severity of sentencing. We therefore reject the government’s argument that Hoffman’s Fifth Amendment claim is barred by Teague, and proceed to consider the claim on the merits.
Hoffman’s Fifth Amendment claim is undercut by the fact that Hoffman was advised that he could exercise his Fifth Amendment right to remain silent during the presentence interview. See Hoffman, 73 F.Supp.2d at 1206. Hoffman does not argue on appeal that the damaging statements made during the presentence interview were involuntary in violation of his Fifth Amendment privilege. Cf. Jones, 686 F.2d at 757 (holding statements involuntary where probation officer instructed defendant to answer all questions and questioned defendant about additional criminal activity). We conclude that although the Fifth Amendment privilege applies, it was not violated in the circumstance of this particular case.
B. Hoffman’s Sixth Amendment Claim
The Sixth Amendment guarantees a criminal defendant “the right ... to have the Assistance of Counsel for his defense.” U.S. Const, amend. VI. “[T]he Sixth Amendment right to counsel at[539]*539taches ‘at or after the initiation of adversary judicial criminal proceedings — whether by way of formal charge, preliminary hearing, indictment, information, or arraignment.’ ” United States v. Harrison, 213 F.3d 1206, 1209 (9th Cir.2000) (quoting Kirby v. Illinois, 406 U.S. 682, 689, 92 S.Ct. 1877, 32 L.Ed.2d 411 (1972)). Hoffman’s Sixth Amendment right to counsel attached before trial. See Estelle, 451 U.S. at 469-70, 101 S.Ct. 1866. Once the right has attached, the Sixth Amendment “is violated whenever the accused is denied counsel at a critical stage” of the adversary proceeding. United States v. Bohn, 890 F.2d 1079, 1080 (9th Cir.1989) (internal quotations omitted). The Supreme Court has long recognized sentencing as a critical stage. See, e.g., Gardner v. Florida, 430 U.S. 349, 358, 97 S.Ct. 1197, 51 L.Ed.2d 393 (1977) (“[I]t is now clear that the sentencing process, as well as the trial itself, must satisfy the requirements of the Due Process Clause.... [T]he sentencing is a critical stage of the criminal proceeding at which [the defendant] is entitled to the effective assistance of counsel.”). The issue in this case is whether the presen-tence interview conducted by a probation officer in preparation for the capital sentencing hearing constitutes a “critical stage” of the judicial proceedings.
Hoffman again relies on Estelle for his claim that he was denied his Sixth Amendment right to counsel during the presentence interview. As set forth above, the Supreme Court held in Estelle that the defendant’s right to counsel extended to an interview with a court-appointed psychiatrist prior to sentencing. 451 U.S. at 469-70, 101 S.Ct. 1866. The Court reasoned that the interview played a significant role in sentencing, and thus constituted a “critical stage” for the purpose of the Sixth Amendment analysis. Id. at 470-71, 101 S.Ct. 1866. Hoffman contends that Estelle governs his case, because like the defendant in Estelle, Hoffman faces sentencing, “literally a life or death matter,” based on information gathered in an interview conducted without the benefit of counsel. See id. at 471, 101 S.Ct. 1866.
The state argues that this court’s decision in Baumann v. United States, 692 F.2d 565 (9th Cir.1982), forecloses the application of Estelle to presentence interviews in capital cases, and that any decision to the contrary would violate Teague. We read Baumann differently. The defendant in Baumann was sentenced to a five-year prison term on four counts of mail fraud. 692 F.2d at 569. Baumann relied on Estelle and challenged the lack of counsel during his presentence interview as a denial of his Sixth Amendment right. Id. at 574. We rejected Baumann’s claim, declining to characterize a “routine” pre-sentence interview as a critical stage. Id. at 578. We similarly rejected Baumann’s Fifth Amendment claim that he was entitled to full Miranda warnings before submitting to a presentence interview. Id. at 576.
We reached our Fifth and Sixth Amendment conclusions in Baumann by distinguishing the capital bifurcated jury proceeding in Estelle from Baumann’s “noncapital,” “routine” sentencing. 692 F.2d at 576-78. We noted that the question of whether the defendant in Bau-mann was entitled to Fifth and Sixth Amendment protection during the non-capital presentence interview had some “similarity to the [question] advanced in Estelle,” but read Estelle “narrowly” and found that the force of Estelle’s reasoning was “limited to the distinct circumstances of [ ] bifurcated capital proceedings.” Id. at 575-76.
Our decision in Baumann not to apply the Fifth and Sixth Amendment rights to counsel to routine presentence interviews with probation officers rested on the “substantial differencefs]” in sentencing procedure and stakes between capital and routine cases. See id. at 576. By distinguishing the procedures required in capital presentence stages from those permitted in non-capital presentence interviews, Baumann joined a long line of cases re[540]*540quiring heightened procedural safeguards in capital cases. See Lankford v. Idaho, 500 U.S. 110, 125-27, 111 S.Ct. 1723, 114 L.Ed.2d 173 (1991) (weighing the “special importance of fair procedure in the capital sentencing context” and holding that the lack of notice to the defendant of Idaho’s intent to seek the death penalty violated Due Process); Eddings v. Oklahoma, 455 U.S. 104, 111, 113-15, 102 S.Ct. 869, 71 L.Ed.2d 1 (1982) (discussing heightened protections in capital cases and reversing death sentence because the jury was not permitted to consider all of the capital defendant’s mitigating character evidence); Beck v. Alabama, 447 U.S. 625, 637-38, 100 S.Ct. 2382, 65 L.Ed.2d 392 (1980) (noting the Court’s “often stated” principle that “there is a significant constitutional difference between the death penalty and lesser punishments,” and overturning death sentence because the jury was not instructed on a lesser included noncapital offense); Woodson v. North Carolina, 428 U.S. 280, 305, 96 S.Ct. 2978, 49 L.Ed.2d 944 (1976) (finding that “the penalty of death is qualitatively different from a sentence of imprisonment,” and therefore holding North Carolina’s mandatory death penalty statute unconstitutional).
We also limited the holding of Baumann in federal cases in United States v. Herrera-Figueroa, 918 F.2d 1430 (9th Cir.1991). In Herrera-Figueroa we exercised our supervisory power to require that probation officers permit defense attorneys to accompany defendants in all presentence interviews. See id.
We find that a presentence interview in a capital case is a “critical stage” for the purpose of the Sixth Amendment’s right to counsel. This conclusion is compelled by the principle from Estelle that defendants should not face presentencing stages in capital cases without the benefit of counsel, and the Baumann distinction between capital and non-capital cases.24 The presentence interview is a mandatory part of Idaho’s capital sentencing scheme and forms the basis of the presentence report, considered by the court during sentencing. “Given the gravity of the decision to be made at the penalty phase, the State is not relieved of the obligation to observe fundamental constitutional guarantees.” Estelle, 451 U.S. at 463, 101 S.Ct. 1866. The stakes for the defendant and for society are too high to allow defendants to face this important component of the sentencing process without the “guiding hand of counsel.” Id. at 471, 101 S.Ct. 1866. We find that this conclusion is dictated by Supreme Court and Ninth Circuit precedent available at the time of Hoffman’s conviction, and thus conclude that Teague does not apply.
Turning to the merits of Hoffman’s claim, we conclude that Hoffman was denied his Sixth Amendment right to counsel during the presentence interview. The next step of our analysis is to ask whether this constitutional violation is “harmless error.” Satterwhite v. Texas, 486 U.S. 249, 256, 108 S.Ct. 1792, 100 L.Ed.2d 284 (1988). We apply the standard from Brecht v. Abrahamson, 507 U.S. 619, 113 S.Ct. 1710, 123 L.Ed.2d 353 (1993), to Hoffman’s habeas petition, and ask whether Hoffman established that the “error had a substantial and injurious effect” on his sentence. See Bains v. Cambra, 204 F.3d 964, 977 (9th Cir.2000) (holding that the Brecht harmless error standard applies in all federal habeas corpus cases under § 2254).
We cannot adequately evaluate the impact of Hoffman’s incriminating statements made during the presentence interview without considering the full body [541]*541of mitigating and aggravating evidence considered at sentencing. Hoffman’s allegations of ineffective assistance of counsel at the trial and sentencing cast doubt over the reliability of this body of evidence; he alleges that damaging information would have been excluded and beneficial information admitted had he received effective assistance of counsel. If Hoffman proves these allegations at the ineffectiveness hearing, then Hoffman’s statements made during the presentence interview, without the benefit of counsel, may be sufficiently damaging to constitute error. We therefore remand the question whether the denial of counsel at the presentence hearing constituted “harmless error” based, in part, on relevant evidence that may be developed at the hearing to determine whether Hoffman was denied effective assistance of counsel.
IV.
Application of the “Heinous, Atrocious or Cruel” Aggravating Factor
Hoffman alleges that during sentencing the trial court relied upon an unconstitutionally vague aggravating factor, “that the murder was especially heinous, atrocious or cruel, manifesting exceptional depravity.” Idaho Code § 19 — 2515(h)(5). Hoffman contends that the Idaho Supreme Court’s construction of this factor fails to narrow sufficiently the sentencer’s discretion as required by the Eighth and Fourteenth Amendments. He asserts that the “heinous, atrocious or cruel” aggravating factor fails to pass constitutional muster for the same reasons that the United States Supreme Court found Oklahoma’s “especially heinous, atrocious, or cruel” aggravating factor invalid in Maynard v. Cartwright, 486 U.S. 356, 363-64, 108 S.Ct. 1853, 100 L.Ed.2d 372 (1988). We do not reach the merits of this claim because we conclude that the trial court’s consideration of the challenged sentencing factor would constitute harmless error, assuming that the factor is unconstitutional.
The appropriate remedy for reliance upon an unconstitutional aggravating factor depends in part on whether the state statute is a weighing or non-weighing statute.25 Generally, in states with non-weighing schemes, reviewing courts may affirm the sentence if other valid aggravating factors remain. See Williams v. Calderon, 52 F.3d 1465, 1477 (9th Cir.1995); cf. Tuggle v. Netherlands 516 U.S. 10, 13-14, 116 S.Ct. 283, 133 L.Ed.2d 251 (1995) (clarifying that this rule does not permit affirmance in cases where the constitutional taint of the illegitimate factor infects the other factors). A court reviewing a sentence imposed under a weighing scheme must conduct constitutional harmless-error analysis or require a reweighing. See Williams, 52 F.3d at 1477.26
At the time of Hoffman’s conviction, the Idaho death penalty statute required the sentencing court to weigh the aggravating circumstances against the mitigating circumstances. See, Williams, 52 F.3d at 1478 n. 13 (“Idaho has been treated as a weighing state because of the explicit procedural constraint.”); Beam v. Paskett, 3 F.3d 1301, 1310 n. 10, overruled on other grounds by Lambright v. Stewart, 191 F.3d 1181 (9th Cir.1999) (noting that Idaho statute requires courts to weigh each aggravating factor against all mitigating factors). We therefore apply harmless-error analysis and ask whether the allegedly invalid aggravating factor had a “substantial [542]*542and injurious effect or influence” on the court’s determination. Williams, 52 F.3d at 1476.
The trial court in Hoffman’s case independently weighed the mitigating evidence against two statutory aggravating circumstances: one, the unchallenged circumstance, the victim’s status as a potential witness in a legal proceeding, and two, the challenged heinous, atrocious, and cruel circumstance. See Idaho Code § 19-2515(h)(5) and (10). The court determined that each aggravating circumstance, standing alone, outweighed the mitigating evidence. We conclude that any error that arose from the court’s consideration of the heinous, atrocious and cruel aggravating factor did not affect the court’s determination, and constitutes harmless error.
V.
Hoffman’s Claim That the Jury Should Determine the Presence of Aggravating Circumstances