The petitioner-appellant, Charles Edward Hartman, was convicted of first-degree murder and sentenced on May 23, 1983, to death by electrocution. His conviction and sentence were affirmed by this Court in State v. Hartman, 703 S.W.2d 106 (Tenn.1985), cert. denied 478 U.S. 1010, 106 S.Ct. 3808, 92 L.Ed.2d 721 (1986). On January 28, 1987, Hartman filed the post-conviction petition that is the subject of this appeal. In it, he raised numerous issues, including ineffective assistance of counsel during the sentencing phase and prosecutorial misconduct resulting in a violation of his constitutional rights under Massiah v. United States, 377 U.S. 201, 84 S.Ct. 1199, 12 L.Ed.2d 246 (1964), and Brady v. Maryland, 373 U.S. 83, 83 S.Ct. 1194, 10 L.Ed.2d 215 (1963). The post-conviction court found no merit in any of the issues presented and dismissed the petition. The Court of Criminal Appeals modified the judgment of the trial court and affirmed it as modified.1 We granted review in this cause under Rule 11, Tenn.R.App.P., chiefly to consider the two above-described issues.
We now affirm the judgment of the Court of Criminal Appeals insofar as it upholds the conviction and vacates the sentence. The cause is remanded to the trial court for further sentencing proceedings.
As to the numerous issues raised, the primary one concerns the petitioner’s allegations that the State violated his Sixth Amendment right to counsel. In particular, after he had been indicted and had retained counsel, the State arranged with his cellmate, Kenny King, and with another inmate, Raven “Snake” Frazier, to engage petitioner in conversations concerning the charges for the purpose of obtaining incriminating statements for use against him at trial. Ancillary to this claim, the petitioner alleged that the State failed to disclose, as part of the pretrial discovery process, that it had paid King $1000 for his efforts in procuring Frazier as an “independent” witness; the petitioner contended that this failure violated his right to due process. Also, the petitioner alleged several instances of ineffective assistance of trial counsel, and the most troubling one concerns trial counsel’s failure to prepare adequately for the sentencing hearing. Moreover, in his application for Rule 11 review, petitioner asserted that the felony aggravating circumstance described in Tenn. Code Ann. § 39 — 2—203(i)(7) could not constitutionally be used to support the death penalty in this cause.2
*97On appeal, a majority of the Court of Criminal Appeals affirmed the trial court’s judgment; however, it vacated the jury-imposed death sentence and imposed a sentence of imprisonment for life. This modification is subject to the district attorney general’s approval. If the district attorney general were to disapprove, a new sentencing hearing would be conducted. While the majority of the intermediate court agreed with the disposition of the case, each panel member based his opinion upon different grounds.
Judge Allen R. Cornelius, Jr., the author of the court’s opinion, concluded that the petitioner had indeed received the effective assistance of counsel at all stages of the proceedings. He concluded also that through its role in recruiting King and Frazier to elicit incriminating statements from petitioner, the State had violated petitioner’s Sixth Amendment right to counsel. Judge Cornelius ruled that Frazier’s testimony should not have been admitted at the trial. Nevertheless, he reasoned that because the record contained otherwise sufficient evidence upon which the jury could have based its finding of guilt, its consideration of this testimony at the guilt-innocence stage of the trial was harmless error. However, because the nature of the testimony was “highly prejudicial and shocking,” Judge Cornelius found that the testimony could have prejudiced the jurors during the penalty stage. Accordingly, the court vacated the death sentence.
Although he concurred with Judge Cornelius in vacation of sentence, Judge John K. Byers disagreed that the introduction of Frazier’s testimony was constitutional error. Instead, he concluded that trial counsel had been ineffective during the penalty stage of the trial because he had failed to adequately prepare for it. Judge Robert K. Dwyer, the third member of the panel, found no constitutional violation at all and dissented. He would have affirmed the judgment of conviction and the sentence.
Upon review of the record, we agree with Judge Byers’s conclusion that the admission of Frazier’s testimony did not violate the petitioner’s constitutional rights. We hold, however, that the sentence must be vacated and the cause remanded for resen-tencing under this Court’s decisions in State v. Middlebrooks, 840 S.W.2d 317 (Tenn.1992), State v. Howell, 868 S.W.2d 238 (Tenn.1993), and State v. Bigbee, 885 S.W.2d 797 (Tenn.1994). The issue of whether the Court of Criminal Appeals has authority to reduce a death sentence to life imprisonment has yet to be decided. We do not reach that issue, however, because in light of our remand the issue is moot. Because resentencing is required, we need not address the issue of trial counsel’s effectiveness at the sentencing stage. In all other things, the judgment of the Court of Criminal Appeals is affirmed.
I
To better understand this case, a summary of the evidence presented at the original trial is helpful. On November 16, 1981, between the hours of 8:30 and 9:30 p.m., sixteen-year-old Kathy Nishiyama disappeared while driving from her boyfriend’s home south of Clarksville to her home north of the city. Clarksville is located in Montgomery County, which adjoins Dickson and Houston counties. On that date, the petitioner was an inmate of the Dickson County jail. He held “trusty” status there, and his duties included the care and maintenance of the sheriffs patrol cars. On the evening of November 16, the petitioner ehauffeured a sheriffs deputy in patrol car five to his home. The deputy then directed the petitioner to drive the car back to the Dickson County jail. Instead, petitioner refused to follow this directive and continued to drive the patrol car in Dickson and Montgomery counties. Although the petitioner drove away from the deputy’s house in the patrol car at approximately 5:30 p.m., he did not return to the Dickson County jail until almost 3 a.m. the next morning.
Between 6 p.m. and 8 p.m. on the same evening, three Montgomery County residents were individually pulled over by a man in *98civilian clothes driving a patrol car. This man claimed to be an “undercover police officer.” On each occasion, the “officer” asked for directions to Dickson. Two of these residents identified petitioner in court as the man who had pulled them over. Between 9:15 p.m. and 9:30 p.m. that night, a patrol car was observed by several persons as it travelled in Clarksville on Riverside Drive, which is located within two or three miles of the place the victim’s car was found.
One of the persons who saw the patrol car was Roger Meekley, a Clarksville detective. He first saw the car as it travelled north on Riverside Drive in the same direction the victim could have taken to reach her home. Then, about fifteen minutes later, he saw the same car head south on Riverside Drive and turn onto Highway 48/13 to Dickson. Although he could not positively identify the petitioner at trial as the driver of the ear, he did describe the driver as a white male with “longish” brown hair, wearing a green army fatigue-type jacket. This description comported with the petitioner’s physical characteristics at that time and with the clothing he wore that night.
At approximately 10 p.m. that evening, a second person observed a patrol car stopped beside a small brown car (a description consistent with the victim’s ear) at the same location where the victim’s car was ultimately found. A man in civilian clothes was standing beside the car and peering into it. This witness could not identify the petitioner as the man standing beside the car, nor could he identify the patrol ear as Dickson County patrol car five. However, the dispatch records of neither the Montgomery County Sheriff nor the Clarksville Police reflect a traffic stop made at this location on that evening.
While investigating the victim’s disappearance, authorities learned that the petitioner had been joyriding in a Dickson County Sheriffs patrol car that same night. John Cox, an agent employed by the Federal Bureau of Investigation, went to the Dickson County jail to interview the petitioner. The petitioner made several statements during the interview with Cox: first, that he had not been in Clarksville that night; second, that he did not know the Clarksville area well; and third, that during the night the patrol car ended up in a creek and Willie Harrell, an acquaintance, had towed it out. Each of these statements was subsequently contradicted by testimony offered at trial.
Noteworthy also is the testimony of a number of Dickson County Sheriffs deputies about their observations of a blood-like substance smeared near the trunk on the rear right fender of patrol ear five upon its return. Authorities did not determine that the victim was dead until her body was found in a remote wooded area in Houston County three and one half months later.
Included in the cogent evidence arrayed against the petitioner was the testimony of Frazier. Frazier testified at trial that the petitioner had made a number of incriminating statements to him while they were incarcerated at the Main Prison in Nashville. According to Frazier, the petitioner told him that he turned the patrol car’s blue lights on while driving behind the victim and that when she pulled over, he told her there was sickness in her family and that she needed to come with him. Frazier testified that the petitioner bragged that he had raped the victim — before and after he had killed her.
II
At the post-conviction hearing, four persons involved in the education of incriminating statements from the petitioner testified. The first of these was Jack Hestle, the District Attorney General for Montgomery County at the time of the crime; he entered private practice in September 1982. The second was Richard Fisher, an Assistant District Attorney General for Davidson County. Although Fisher had prosecuted King in the past, King trusted him. Another witness was Pat McCutehen, Hestle’s successor as the District Attorney General for Montgomery County; his office prosecuted this case. The fourth witness was Wade Bobo, the Assistant District Attorney General primarily responsible for the investigation and trial of this case under MeCutchen’s supervision.
Hestle testified that in late 1982 or early 1983, he was contacted by Frazier, an inmate *99at the Main Prison in Nashville. Frazier was serving a sentence for second-degree murder and was soon to have a clemency hearing. Frazier told him that the petitioner had made incriminating statements to him about the Nishiyama ease. He asked Hestle whether he thought it would improve his chances for clemency were he to obtain information about the Nishiyama case. Hestle advised him that he thought it might help.
At about the same time, King contacted Fisher and told him the petitioner had made incriminating statements about the case to him. King indicated an interest in any reward money offered. Fisher relayed this information to Hestle, who in turn contacted McCutchen and Bobo; he told them that the petitioner had apparently made incriminating statements to Frazier and Kong.
Thereafter, McCutchen, Bobo, and Fisher went to the Main Prison. On this first trip, Fisher went inside and talked to King. King made it clear to Fisher that he would not testify, but for $1000, he would attempt to record an incriminating conversation with the petitioner on audio tape and would provide a third-party witness to testify at trial. During this visit, King revealed a few details that the petitioner had told him. These included that the victim had been raped and that racial bias had been a motivation. Fisher relayed this information to McCutchen and Bobo; they agreed to provide the money King had demanded.
The next visit to the Main Prison occurred about two weeks before trial when Hestle and Bobo met with Frazier and then King. Frazier told them the petitioner had related details of the killing to him, including that the petitioner had raped the victim after he had slain her. When they met with King, he furnished other information about the incident, including the statement that the petitioner had used the blue lights of the patrol car to pull the victim over and had persuaded her to get into the ear with him by telling her that a member of her family was sick. During this visit, King agreed to attempt to record the petitioner’s statements on audio tape and to have a third party present (presumably Frazier) to authenticate the tape and testify at trial.
During a third visit a few days before trial, King reported that the tape recorder had malfunctioned, thereby thwarting the plan to record the conversation on tape. Nevertheless, Frazier confirmed that he had heard the petitioner make incriminating statements in King’s presence and agreed to testify in return for protection from physical harm. Frazier testified at trial, and the petitioner was convicted and sentenced to death. After trial, $1000 was deposited to King’s prison account as payment for his role in producing Frazier as a witness.
Ill
The law is clear that the Sixth Amendment right to counsel attaches to all critical stages of a prosecution. “[0]nce adversary proceedings have commenced against an individual, he has a right to legal representation when the government interrogates him.” Brewer v. Williams, 430 U.S. 387, 401, 97 S.Ct. 1232, 1240, 51 L.Ed.2d 424 (1977) (citing Massiah v. United States, 377 U.S. 201, 84 S.Ct. 1199, 12 L.Ed.2d 246 (1964)). The United States Supreme Court has held that where government agents alerted a cooperating inmate to listen for any incriminating statements from an accused, even such passive conduct may be imputable to the government. The Court, in United States v. Henry, 447 U.S. 264, 275, 100 S.Ct. 2183, 2189, 65 L.Ed.2d 115 (1980), characterized such conduct on the part of government agents as a planned, “impermissible interference with the right to assistance of counsel.”
Once the right to counsel has attached and been asserted, the State must of course honor it. This means more than simply that the State cannot prevent the accused from obtaining the assistance of counsel. The Sixth Amendment also imposes on the State an affirmative obligation to respect and preserve the accused’s choice to seek this assistance. We have on several occasions been called upon to clarify the scope of the State’s obligation in this regard, and have made clear that, at the very least, the prosecutor and police have an affirmative obligation not to act in a manner that circumvents and thereby dilutes the protection afforded by the right to counsel.
*100Maine v. Moulton, 474 U.S. 169, 170-171, 106 S.Ct. 477, 484, 88 L.Ed.2d 481 (1986) (footnote omitted).
There is no question that petitioner’s Sixth Amendment right to counsel had attached at the time prosecutors talked with King and Frazier about the recording of petitioner’s statements. Petitioner had already been indicted and had been represented by counsel for months. He was clearly entitled to rely on counsel as a “medium” between himself and the State. See Michigan v. Jackson, 475 U.S. 625, 106 S.Ct. 1404, 89 L.Ed.2d 631 (1986); Maine v. Moulton, 474 U.S. at 176, 106 S.Ct. at 487 (1985). Also, once King and Frazier had been approached by Bobo about recording any subsequent statements made by the petitioner, they were clearly acting as agents of the State.
[KJnowing exploitation by the State of an opportunity to confront the accused without counsel being present is as much a breach of the State’s obligation not to circumvent the right to the assistance of counsel as is the intentional creation of such an opportunity. Accordingly, the Sixth Amendment is violated when the State obtains incriminating statements by knowingly circumventing the accused’s right to have counsel present in a confrontation between the accused and a state agent.
Maine v. Moulton, 474 U.S. at 176,106 S.Ct. at 487 (citation omitted). Therefore, any statements made by the petitioner to the two inmates after they had been recruited by the State would be inadmissible. Massiah v. United States, 377 U.S. 201, 84 S.Ct. 1199, 12 L.Ed.2d 246; State v. Webb, 625 S.W.2d 259 (Tenn.1981), cert. denied, 456 U.S. 910, 102 S.Ct. 1760, 72 L.Ed.2d 168 (1982); State v. Berry, 592 S.W.2d 553 (Tenn.1980), cert. denied, 449 U.S. 887, 101 S.Ct. 241, 66 L.Ed.2d 112 (1980).
The fact remains, however, that Frazier heard the petitioner make incriminating statements before he first contacted the authorities. Frazier had communicated with Hestle (and King with Fisher) to the effect that the petitioner had been bragging about the details of the crime before either of them ever met with the prosecutors. Actually, these communications precipitated the meetings with King and Frazier in the first place. Any admissions made by the petitioner before law enforcement authorities became involved would, of course, be admissible. As the U.S. Supreme Court has noted: “the Sixth Amendment is not violated whenever— by luck or happenstance — the State obtains incriminating statements from the accused after the right to counsel has attached.” Maine v. Moulton, 474 U.S. at 176, 106 S.Ct. at 487 (emphasis added).
From the testimony at the post-conviction hearing, no distinction appears between those details Frazier heard before he contacted Hestle and those he heard after becoming involved with the prosecutors. However, both Hestle and Bobo testified that their conversation with Frazier about obtaining petitioner’s statement occurred after the petitioner had bragged to Frazier that he had raped the victim. Bobo recalled that it was King, not Frazier, who informed them that the petitioner had told him he had used the blue lights of the patrol car to pull the victim over. It is unclear from the record when Frazier heard this detail. Even if Frazier did not know of this particular detail before entering the State’s employ, any error in admitting this portion of his testimony is subject to a harmless-error analysis. State v. Sparks, 727 S.W.2d 480, 482 (Tenn.1987), cert. denied, 484 U.S. 872, 108 S.Ct. 205, 98 L.Ed.2d 156 (1987); see also, United States v. Henry, 447 U.S. at 275, 100 S.Ct. at 2189 (footnote 13). Additionally, other cogent testimony supports the State’s theory that the petitioner abducted the victim by using the blue lights of the patrol car to cause the victim to pull over. Three Montgomery County residents testified that a Dickson County “undercover officer” had pulled them over that same night by using the blue lights on the patrol car; two of these witnesses were able to identify the petitioner at trial as the person who had pulled them over. Moreover, another witness observed a county patrol car next to a car matching the description of the victim’s car at the very spot where the victim’s car was ultimately found. This witness described a man standing beside the *101car as fitting the general appearance of the petitioner. Therefore, any testimony by Frazier that the petitioner used the car’s blue lights to stop the victim, even if told to him after entering State “employ,” was harmless beyond a reasonable doubt. His remaining testimony, unquestionably having been obtained before he ever spoke with the prosecutors, was admissible. Accordingly, petitioner’s claim that this testimony violated his Sixth Amendment right to counsel is without merit.
IV
Petitioner claims that he was denied his right to confront the witnesses against him and asserts thereby that his due process right to a fair trial was violated because the State failed to inform him of the agreement to pay King to produce a witness to petitioner’s incriminating statements. The State’s case against the petitioner was strong indeed, but the only direct evidentiary link between the victim and the petitioner was the testimony of Frazier.
The United States Supreme Court has held that:
the suppression by the prosecution of evidence favorable to an accused upon request violates due process where the evidence is material either to guilt or to punishment, irrespective of the good faith or bad faith of the prosecution.
Brady v. Maryland, 373 U.S. 83, 87, 83 S.Ct. 1194, 1196-97, 10 L.Ed.2d 215 (1963); see also, State v. Davis, 823 S.W.2d 217, 219 (Tenn.Crim.App.1991). The Court has specifically held that evidence impeaching a government witness’s credibility may be exculpatory within the meaning of Brady. “When the reliability of a given witness may well be determinative of guilt or innocence, nondisclosure of evidence affecting credibility falls within this general rule.” Giglio v. United States, 405 U.S. 150, 154, 92 S.Ct. 763, 766, 31 L.Ed.2d 104 (1972) (quoting Napue v. Illinois, 360 U.S. 264, 269, 79 S.Ct. 1173, 1177, 3 L.Ed.2d 1217 (1959)). “Such evidence is ‘evidence favorable to an accused,’ Brady, 373 U.S. at 87[, 83 S.Ct. at 1196], so that, if disclosed and used effectively, it may make the difference between conviction and acquittal.” United States v. Bagley, 473 U.S. 667, 676, 105 S.Ct. 3375, 3380, 87 L.Ed.2d 481 (1985); see also, State v. Williams, 690 S.W.2d 517, 525 (Tenn.1985).
Promises made by the state to a witness in exchange for his testimony relate directly to the credibility of the witness. A prosecutor has a duty to disclose evidence of any promises made by the state to a prosecution witness in exchange for his testimony.... This is especially true when the testimony of the witness is essential to the state’s case.
Moore v. Kemp, 809 F.2d 702, 719 (11th Cir.1987), cert. denied, 481 U.S. 1054, 107 S.Ct. 2192, 95 L.Ed.2d 847 (1987).
As stated, the circumstantial evidence against petitioner was strong, even without the questioned testimony. Frazier’s testimony, however, was the linchpin: that is, it served to tie the circumstances together and to provide contextual meaning. Clearly, any evidence that Frazier had been paid, promised clemency, or given any benefit whatsoever for his testimony should have been provided to defense counsel. The facts related at the post-conviction hearing, however, indicate that for his testimony Frazier received only the promise of protection from reprisal by other inmates. Bobo testified that the money was entirely King’s. Trust account records at the prison reflect that the entire $1000 was deposited into King’s account. The trial court found as a matter of fact that no evidence was introduced to prove that King shared or agreed to share the money with Frazier. In spite of our grave misgivings about testimony obtained in this manner, we are constrained to find that the proof offered at the post-conviction hearing fails to support the petitioner’s contention of constitutional violation.
The petitioner suggests that McCutchen’s and Bobo’s later support for Frazier’s clemency bid — McCutehen by writing a letter and Bobo by testifying at the clemency hearing— is evidence of a prior agreement. Each admitted having supported Frazier’s clemency petition but denied that their support was in any way conditioned upon Frazier testifying at trial. Apparently, while Frazier may have hoped that his testimony at the petitioner’s *102trial would result in favorable treatment at his clemency hearing, no evidence of any promise made for such favorable treatment was adduced.3 The only promise made to Frazier was that he would be protected from other inmates after he testified; this area was fully explored at trial during Frazier’s cross-examination.
The question remains whether the fact that King, who did not testify at trial, received payment for helping the prosecution should have been disclosed to defense counsel. The United States Supreme Court has injected a “materiality” requirement into the rule that exculpatory information be provided to a defendant.
[I]f the subject matter of such a [Brady ] request is material, or indeed if a substantial basis for claiming materiality exists, it is reasonable to require the prosecutor to respond either by furnishing the information or by submitting the problem to the trial judge.
United States v. Agurs, 427 U.S. 97, 106, 96 S.Ct. 2392, 2399, 49 L.Ed.2d 342 (1976).
[I]mplieit in the requirement of materiality is a concern that the suppressed evidence might have affected the outcome of the trial....
[U]nless the omission deprived the defendant of a fair trial, there is no constitutional violation requiring that the verdict be set aside; and absent a constitutional violation, there was no breach of the prosecutor’s constitutional duty to disclose_
The mere possibility that an item of undisclosed information might have helped the defense, or might have affected the outcome of the trial, does not establish “materiality” in the constitutional sense....
The proper standard of materiality must reflect our overriding concern with the justice of the finding of guilt. Such a finding is permissible only if supported by evidence establishing guilt beyond a reasonable doubt. It necessarily follows that if the omitted evidence creates a reasonable doubt that did not otherwise exist, constitutional error has been committed. This means that the omission must be evaluated in the context of the entire record. If there is no reasonable doubt about guilt whether or not the additional evidence is considered, there is no justification for a new trial. On the other hand, if the verdict is already of questionable validity, additional evidence of relatively minor importance might be sufficient to create a reasonable doubt.
United States v. Agurs, 427 U.S. at 104—113, 96 S.Ct. at 2398-2402. “Materiality” has more recently been defined as that which undermines confidence in the outcome of the trial.
The evidence is material only if there is a reasonable probability that, had the evidence been disclosed to the defense, the result of the proceeding would have been different. A ‘reasonable probability1 is a probability sufficient to undermine confidence in the outcome.
United States v. Bagley, 473 U.S. at 682,105 S.Ct. at 3383, accord, State v. Davis, 823 S.W.2d at 219.
We find the payment of $1000 to King to be immaterial. King did not testify; his credibility was not an issue at this trial. In light of the fact that Frazier had approached Hestle on his own before any discussion of payment to King occurred, the connection between Frazier and the money is tenuous at best. Therefore, the failure of the State to disclose this information to defense counsel did not in any way deprive the petitioner of a fair trial.
V
The petitioner was convicted of first-degree murder in the perpetration of the felony of kidnapping. The jury found three aggravating circumstances to justify imposition of the death penalty: (1) that the murder was especially heinous, atrocious or cruel in that it involved torture or depravity of mind; (2) that the murder was committed while the defendant was engaged in committing a felony (kidnapping); and (3) that the murder was committed by the defendant while he was in lawful custody or in a place *103of lawful confinement or during his escape from lawful custody or from the place of lawful confinement.
Subsequent to the opinion of the Court of Criminal Appeals in this case, this Court released State v. Middlebrooks, 840 S.W.2d 317 (Tenn.1992). In Middlebrooks, a majority of the Court held unconstitutional the use of the aggravating circumstance described in Tenn.Code Ann. § 39 — 2—20B(i)(7) [now § 39-13-204(i)(7) ]4 to support imposition of the death penalty for a conviction of first-degree murder committed in the commission of a felony. We determined that in such conviction, the use of this aggravating circumstance failed to narrow the class of death-eligible murderers as required by Article I, § 16, of the Tennessee Constitution. Inasmuch as the constitutional rule announced in Middlebrooks enhances the integrity and reliability of the fact-finding process of the trial, it must be applied retroactively in post-conviction proceedings. See Meadows v. State, 849 S.W.2d 748, 754 (Tenn.1993); Barber v. State, 889 S.W.2d 185 (Tenn.1994). Thus, the jury in this case relied, in part, upon an invalid aggravating circumstance in determining punishment.
Nevertheless, neither the United States nor the Tennessee constitution prohibits a reviewing court from upholding a death sentence that is based in part on an invalid aggravating circumstance. To guarantee that a defendant will receive an individualized sentence, however, the reviewing court must either reweigh the aggravating and mitigating evidence or conduct a harmless-error review. Stringer v. Black, 503 U.S. 222, 112 S.Ct. 1130, 117 L.Ed.2d 367 (1992); Clemons v. Mississippi, 494 U.S. 738, 110 S.Ct. 1441, 108 L.Ed.2d 725 (1990); State v. Cazes, 875 S.W.2d 253 (Tenn.1994); State v. Howell, 868 S.W.2d 238 (Tenn.1993).
We now review for harmless error and must now determine, based on the facts here present, whether the jury’s consideration of the invalid aggravator constituted harmless error beyond a reasonable doubt. In State v. Howell, 868 S.W.2d at 260-261, we held that:
[i]n order to guarantee the precision that individualized sentencing considerations demand and provide a principled explanation for our conclusion in each ease, it is important, when conducting harmless error review, to completely examine the record for the presence of factors which potentially influence the sentence ultimately imposed. These include, but are not limited to, the number and strength of remaining valid aggravating circumstances, the prosecutor’s argument at sentencing, the evidence admitted to establish the invalid aggravator, and the nature, quality and strength of mitigating evidence.
Initially, we point out that several factors here would appear to support a finding of harmless error under Howell. First, no additional evidence, nor any evidence that was not already properly before the jury, was introduced in support of the invalid aggravator. Moreover, the prosecutor did not emphasize the invalid aggravator in his jury argument. Furthermore, there was only minimal proof of mitigating circumstances. However, we cannot conclude, after a thorough review of the record, that the sentence would have been the same had the jury accorded no weight to the invalid aggrava-tors. We reach this result because of our assessment of the remaining aggravators.
In Howell, we noted that a critical factor in our harmless-error analysis was the qualitative nature of each aggravating circumstance that remained after the invalid aggravator was removed from the sentencing equation. This Court stated an intention to look to the substance of the remaining circumstances and their persuasiveness, as well as to the quantum of proof supporting them. The objective reliability of a remaining aggravating circumstance is of particular importance in this evaluation. Id.
In this case, there are two remaining ag-gravators: the “heinous, atrocious or cruel” *104nature of the offense, Tenn.Code Ann. § 39-2-203(i)(5), and the petitioner’s status as an “escapee”- at the time of the crime, Tenn. Code Ann. § 39-2-203(i)(8). The record in this case supports the second of these two aggravators, which is purely objective in nature. The proof is uncontradicted that the petitioner was in the constructive custody of the Dickson County Sheriffs Department at the time the victim disappeared. The meaning of this circumstance and its application to the proof presented in this case is certain.
On the other hand, the other aggravator (“heinous, atrocious or cruel”) is less objective in nature. This Court has sought to make it more objective by defining its terms and by requiring that the jury be instructed as to these definitions at the sentencing hearing of any trial where the death penalty is sought on the basis of this particular aggra-vator. See State v. Williams, 690 S.W.2d 517, 529-532 (Tenn.1985). While not error in the present case (see Issue IV, infra), the trial court did not instruct the jury as to these definitions. Also, a substantial amount of the proof presented to support this aggra-vator is included in the testimony of Frazier. While we do not redetermine the credibility of witnesses when conducting a harmless-error analysis of this sort, the fact that the credibility of a witness was so seriously contested is a relevant factor in determining whether we find beyond a reasonable doubt that an error of this nature was harmless. After disregarding the constitutionally invalid aggravator, where the remaining valid ag-gravator is substantially supported by the testimony in question, the harmless effect of the error in admitting the invalid aggravator is much more difficult to determine. Under the circumstances of this case, we are unable to conclude that the sentence would have been the same had the jury given no weight to the invalid aggravator. Accordingly, we remand the cause to the trial court for a new sentencing hearing in which the State may seek either statutory penalty. See State v. Middlebrooks, 840 S.W.2d at 347.
VI
The purpose of the Sixth Amendment requirement for the effective assistance of counsel is to ensure that persons accused of crimes receive a fair trial.
The benchmark for judging any claim of ineffectiveness must be whether counsel’s conduct so undermined the proper functioning of the adversarial process that the trial cannot be relied on as having produced a just result.
Strickland v. Washington, 466 U.S. 668, 686, 104 S.Ct. 2052, 2064, 80 L.Ed.2d 674 (1984). Article I, § 9 of the Tennessee Constitution and the Sixth Amendment to the United States Constitution are identical in import. Baxter v. Rose, 523 S.W.2d 930 (Tenn.1975).
The United States Supreme Court has defined two requirements for a finding that a defendant did not receive the effective assistance of counsel: (1) that counsel’s performance was deficient to the degree that counsel was not functioning as the Sixth Amendment envisioned; and (2) that the deficient performance prejudiced the defense effort. Strickland v. Washington, 466 U.S. at 687, 104 S.Ct. at 2064. The second “requires showing that counsel’s errors were so serious as to deprive the defendant of a fair trial, a trial whose result is reliable.” 466 U.S. at 687, 104 S.Ct. at 2064. To prove deprivation of a fair trial, a defendant must show “that there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different. A reasonable probability is a probability sufficient to undermine confidence in the outcome.” 466 U.S. at 694, 104 S.Ct. at 2068. If counsel’s performance was in some way deficient, but a defendant cannot prove the deficiency prejudiced his defense, then any deficiency is deemed “harmless error,” and counsel will not be held to be ineffective. 466 U.S. at 692, 104 S.Ct. at 2067.
There is a strong presumption that assistance rendered by an attorney falls within the wide range of reasonable professional assistance. The defendant must overcome this presumption of reasonableness, and he must show that the alleged deficiency was unsound trial strategy. 466 U.S. at 689, 104 S.Ct. at 2065. A reviewing court should look to all the circumstances of the case and evaluate the alleged deficiency from trial *105counsel’s perspective. 466 U.S. at 689, 104 S.Ct. at 2065.
Petitioner complains that trial counsel failed to adequately investigate the case, interview witnesses, and present certain testimony at trial. The evidence at the post-conviction hearing, however, reflects that although counsel did not personally interview each of the one hundred fourteen witnesses whose identities had been provided to him before trial, he, co-counsel, or an investigator interviewed most of them before trial. Additionally, even as to the uninterviewed witnesses, the trial record establishes that counsel cross-examined those witnesses vigorously and illuminated discrepancies in their testimony. Moreover, contrary to petitioner’s assertion, counsel did present testimony during the defense case to support the defendant’s theory that the defendant had spent much of his time that evening looking for someone to pull the patrol car out of a creek. In short, we find that counsel’s performance during the guilt phase of the trial was “within the range of competence demanded of attorneys in criminal eases.” Baxter v. Rose, 523 S.W.2d at 936. This issue has no merit.
The petitioner also complains that trial counsel did not adequately voir dire prospective jurors on their respective attitudes about the death penalty. The decision whether to voir dire a prospective juror on this issue, or to what degree, is a strategic one. Valid tactical reasons exist to refrain from asking detailed questions on the death penalty, particularly in a case such as this where the defense is that the state has accused the wrong person. Too intense an inquiry in this regard may be perceived by potential jurors as a concession that credible evidence of guilt exists. Therefore, we cannot find that counsel here was ineffective for failing to delve deeper into this sensitive area. Furthermore, even if counsel’s choice were deemed erroneous, the petitioner has failed to show prejudice. The record reflects the trial court asked each juror about his or her attitudes toward the death penalty. Indeed, this questioning resulted in a number of jurors being excused for cause. Because we find no evidence to indicate that this jury was less than fair or impartial, this issue has no merit.
Petitioner also advances allegations of ineffective assistance of counsel at the sentencing phase of the trial. Because we have determined that a new sentencing hearing is necessary under the holding of State v. Howell, supra, this issue is pretermitted.
During its instructions to the jury on aggravating circumstances, the trial court instructed pursuant to Tenn.Code Ann. § 39-2 — 203(i)(5) [now Tenn.Code Ann. § 39-13-204(i)(5) ]. Specifically, the court instructed that the jury could not impose the death penalty unless it found, beyond a reasonable doubt, “that the murder was especially heinous, atrocious or cruel in that it involved torture or depravity of mind.” The petitioner asserts that this instruction, without more, did not adequately channel the jury’s discretion and is unconstitutionally vague. He cites the case of State v. Williams, 690 S.W.2d 517 (Tenn.1985), for the proposition that the terms “heinous,” “atrocious,” and “cruel” should have been further defined.
The United States Supreme Court has clearly described the results to be sought from the use of aggravating factors: (1) to ensure that the senteneer’s discretion is channeled and limited to minimize the risk of arbitrary and capricious imposition of the death penalty, Arave v. Creech, — U.S. -, 113 S.Ct. 1534,123 L.Ed.2d 188 (1993); Lewis v. Jeffers, 497 U.S. 764,110 S.Ct. 3092, 111 L.Ed.2d 606 (1990); Maynard v. Cartwright, 486 U.S. 356, 108 S.Ct. 1853, 100 L.Ed.2d 372 (1988); Godfrey v. Georgia, 446 U.S. 420, 100 S.Ct. 1759, 64 L.Ed.2d 398 (1980); Gregg v. Georgia, 428 U.S. 153, 96 S.Ct. 2909, 49 L.Ed.2d 859 (1976); and (2) to make sure that the capital sentencing scheme adequately narrows the class of persons eligible for the death penalty, that is, distinguishes those whose conduct deserves capital punishment from those whose conduct does not. Arave v. Creech, supra; Lewis v. Jeffers, supra; Zant v. Stephens, 462 U.S. 862, 103 S.Ct. 2733, 77 L.Ed.2d 235 (1983).
The United States Supreme Court in Gregg v. Georgia held Georgia’s aggravating *106circumstance5 facially constitutional; it was almost identical to the instructions given the jury in the instant case. This Court has consistently held that the language of Tenn. Code Ann. § 39 — 2—203(i)(5) is not unconstitutionally vague or overbroad. State v. Dicks, 615 S.W.2d 126 (Tenn.1981); Strouth v. State, 755 S.W.2d 819 (Tenn.Crim.App.1986). While it is true that in Williams, this Court expressed the preference that juries be fully instructed as to the definitions of those terms,6 this Court has decided many cases since Williams in which the definitions of these terms were not included in the instructions to the jury. In these cases, the Court upheld the use of this aggravator. Some of these cases were tried before Williams, but decided after. See State v. Barber, 753 S.W.2d 659 (Tenn.1988); State v. Zagorski, 701 S.W.2d 808 (Tenn.1985); State v. Duncan, 698 S.W.2d 63 (Tenn.1985). There are, however, cases tried and appealed after Williams in which the definitions of those terms were not given to the jury, yet we upheld the use of the “heinous, atrocious and cruel” aggravator. See State v. Irick, 762 S.W.2d 121 (Tenn.1988); State v. Portetfield, 746 S.W.2d 441 (Tenn.1988). We deem it significant that the Williams case held that this aggravator was not unconstitutionally vague or overbroad. State v. Williams, 690 S.W.2d at 533; see also, State v. Teel, 793 S.W.2d 236 (Tenn.1990); State v. Thompson, 768 S.W.2d 239 (Tenn.1989) (The language “especially heinous, atrocious or cruel” requires, in addition, a finding of “torture or depravity of mind.” The Court held this additional language gave the jury sufficient guidance to prevent arbitrary sentencing.)
We find that the questioned jury instruction used in this case was valid; it provided the jury with guidance sufficient so as to avoid the possibility of an arbitrary or capricious sentence.7 We note, however, that upon remand the trial court should adhere to the Williams holding if its instructions at resentencing include information regarding this aggravator.
We have examined the other issues included in our order granting review. These include allegations of error in instructing the jury that “malice is presumed” and in refusing to admit evidence of petitioner’s innocence (“residual doubt” evidence) at sentencing. We find that any error in instructing the jury that “malice is presumed” is harmless, since the petitioner was convicted of felony murder, not premeditated murder. See State v. McKay, 680 S.W.2d 447, 451 (Tenn.1984). The remaining issue, concerning “residual doubt” evidence, was considered in the petitioner’s direct appeal and resolved against him. See State v. Hartman, 703 S.W.2d at 119; Tenn.Code Ann. § 40-30-112(a).
The decision by the Court of Criminal Appeals is affirmed insofar as it upholds the petitioner’s conviction for first-degree murder and vacates the sentence of death. The cause is remanded to the trial court for further sentencing proceedings.
ANDERSON, C.J., DROWOTA, J., and O’BRIEN, Special Justice, concur. REID, J., concurring and dissenting.. Hartman v. State, No. 01-C-01-9008-CC-00146, 1992 WL 146756 (Tenn.Crim.App. at Nashville, filed June 30, 1992).
. The five other issues included under this Court's order granting review are: ineffective assistance of counsel for failing to investigate and interview witnesses and present their testimony at trial; ineffective assistance of counsel for failing to adequately voir dire prospective jurors concerning their views regarding the death penalty; the trial court’s failure to define the aggravating circumstance in Tenn. Code Ann. *97§ 39-2-203(i)(5) ("heinous, atrocious or cruel"); denial of due process by the trial court’s use of "the presumption shifting Sandstrom jury instruction”; and the trial court's refusal to permit petitioner to introduce evidence of his innocence as a mitigating circumstance at the sentencing phase of his trial.
. Incidentally, Frazier’s petition for clemency was denied.
. Tenn.Code Ann. § 39 — 2—203(i)(7) states: “The murder was committed while the defendant was engaged in committing, or was an accomplice in the commission of, or was attempting to commit, or was fleeing after committing or attempting to commit, any first degree murder, arson, rape, robbery, burglary, theft, kidnapping, aircraft piracy, or unlawful throwing, placing or discharging of a destructive device or bomb
.The text of Georgia's similar aggravating circumstance had the following language: "[that the murder was] outrageously or wantonly vile, horrible or inhuman in that it involved torture, depravity of mind, or an aggravated battery to the victim.” Godfrey v. Georgia, 446 U.S. 420, 100 S.Ct. 1759, 64 L.Ed.2d 398 (1980), later held the application of this circumstance could be unconstitutional when the facts of the case did not support a finding of torture, depravity, or an aggravated battery.
. The Tennessee Pattern Jury Instructions have since been revised to include the definition of the terms "heinous,” "atrocious," "cruel,” and "torture.” See, Tenn.Pattern Jury Instruction-Criminal 7.04 (1992).
. While the trial court's failure to instruct the jury in accord with Williams does not by itself require relief be granted the petitioner under the circumstances of this case, the omission of the Williams definition has been a factor in our determination that the Middlebrooks error was not harmless.
. The trial judge observed in his memorandum opinion that the case "raised a considerable hue and cry, not only because of the depraved rape and murder, but because of the involvement of the Sheriff's Department of Dickson County.”