JUSTICE HARRISON
delivered the opinion of the court:
The defendant, Andrew Maxwell, appeals (134 111. 2d R. 651(a)) the judgment of the circuit court of Cook County dismissing without an evidentiary hearing his amended petition for post-conviction relief, brought pursuant to the Post-Conviction Hearing Act (725 ILCS 5/122 — 1 et seq. (West 1992)). Following a jury trial the defendant was convicted of murder and attempted armed robbery committed on October 26, 1986. He waived his right to a jury for purposes of his capital sentencing hearing, and the trial court imposed a sentence of death on the conviction for murder and a term of 15 years on the conviction for attempted armed robbery. In his direct appeal (People v. Maxwell, 148 Ill. 2d 116 (1992)), this court affirmed his convictions and sentences. Thereafter the United States Supreme Court denied his petition for a writ of certiorari (Maxwell v. Illinois, 506 U.S. 977, 121 L. Ed. 2d 377, 113 S. Ct. 471 (1992)). Challenging the dismissal of his amended petition without an evidentiary hearing, defendant presents 22 issues for our review. For the reasons that follow, we affirm. Because the facts of this case are set forth adequately in the opinion concerning defendant’s direct appeal, we state here only those facts necessary to the disposition of his post-conviction appeal.
A proceeding brought pursuant to the Post-Conviction Hearing Act is not an appeal per se but, rather, a collateral attack on a judgment. People v. Caballero, 126 Ill. 2d 248, 258 (1989). The purpose of the proceeding is to allow inquiry into constitutional issues related to the original conviction that have not or could not have been adjudicated. People v. Whitehead, 169 Ill. 2d 355, 370 (1996). It is the defendant’s burden to show a substantial deprivation of his constitutional rights (Whitehead, 169 Ill. 2d at 370), and determinations made by the circuit court will not be disturbed unless they are manifestly erroneous (People v. Silagy, 116 Ill. 2d 357, 365 (1987)). The defendant is not entitled to an evidentiary hearing unless the allegations of his petition, supported where appropriate by the trial record or accompanying affidavits, make a substantial showing that his rights have been so violated. Caballero, 126 Ill. 2d at 259. In determining whether an evidentiary hearing should be granted, all well-pleaded facts in the petition and in any accompanying affidavits are to be taken as true. Caballero, 126 Ill. 2d at 259.
Initially defendant contends that he was denied his constitutional right to the effective assistance of counsel at the second phase of the sentencing proceeding because counsel failed "to investigate and present available evidence in mitigation.” Specifically, defendant asserts that trial counsel conducted virtually no investigation into his background, failing (1) to investigate his developmental history; (2) to discover and present to the court not only his school records, which would have revealed his intellectual and developmental deficits, but also his medical records as well as records of childhood psychological tests; (3) to obtain a professional drug and alcohol evaluation with which to gauge the extent of his problem with substance abuse; (4) to discover the alcoholism and attendant denial that pervaded his family, which would have been revealed and explained had counsel obtained a comprehensive social history; (5) to obtain any kind of current psychological or psychiatric evaluation; and (6) to interview the defendant himself sufficiently. The defendant’s voluminous amended post-conviction petition, which includes numerous supporting reports and affidavits attached as exhibits, sets forth these claims in detail.
In his amended petition defendant alleges that because trial counsel failed to obtain his school records, counsel did not know of the determination by his school that he was, in defendant’s words, "educably mentally handicapped” and that, as a result, counsel could not make an informed decision as to how this information would affect sentencing. In the same way, defendant alleges, counsel did not know of defendant’s "borderline mentally retarded I.Q.” Similarly, counsel’s failure to obtain a drug and alcohol evaluation of defendant meant that his attorneys were not fully aware of the extent of his problems. Counsel’s failure to interview defendant’s father and his sisters, Monalisa Maxwell and Martha Brown, and to investigate or evaluate drug and alcohol usage in his immediate family prevented counsel from understanding defendant’s drug dependency, his intellectual and developmental deficiencies, and his family’s denial of those problems; as a consequence, defendant alleges, counsel lacked a strategy for mitigation. Defendant alleges finally with respect to this first claim of his amended petition:
"Assuming arguendo that trial counsel was not inadequate for concluding, based on her limited investigation, that [defendant] had not had significant intellectual, physical and developmental deficits, trial counsel was put on notice of these problems by the Presentence Report which had been filed March 11, 1988. [Ex. 17] [sic] Counsel was incompetent for failing to pursue this evidence.”
The defendant includes as an exhibit in support of this claim the affidavit of Louis Hemmerich, Ph.D., a clinical psychologist who tested him on March 14, 1993. The affidavit includes the report of his psychological evaluation. In it the defendant is reported to have stated that he had been held back in the third grade because of a lack of academic progress and that he had been in special education classes during most of his formal education. The defendant also reported having had psychiatric counseling, in Dr. Hemmerich’s words, "for a brief period of time, about six months, when he was in the third or fourth grade.” He described the defendant’s Full Scale score on the Wechsler Adult Intelligence Scale-Revised as being within the borderline mentally retarded range of intellectual ability. The pattern of scores obtained on this administration of the intelligence test suggests, Dr. Hemnierich concluded, that defendant suffers from a verbal information processing learning disability. In his summary he assessed the test results as indicating that defendant was functioning "within the borderline mentally retarded range to the low average range of intellectual ability.”
Dr. Hemmerich stated further that defendant
"reported a serious history of alcohol and drug abuse. He stated that he began smoking marijuana at the age of twelve. At that time, his sisters would encourage him to smoke a joint with them since they enjoyed watching him 'get silly.’ He reportedly began drinking alcohol at approximately the age of 14. At the age of 16, he began using cocaine. During this period of time, he also took codeine, up to three ounces of syrup and three pills at a time. By the age of 17, he admitted to drinking 1h pint of whiskey and smoking a nickel bag of marijuana each night. Later that year, he stated that he would smoke marijuana laced with cocaine. He stated that he had a hard time functioning without using drugs and alcohol, and reportedly used substances on a daily basis.”
Dr. Hemmerich concluded that the amount of drugs and alcohol reportedly consumed, as well as the withdrawal symptoms defendant reported, suggest that he was physiologically addicted to drugs and alcohol. The psychologist reported further that defendant
"stated that he had never participated in any drug or alcohol treatment program. He stated, T never admitted I had a problem.’ He stated that he has experienced numerous legal difficulties due to drug and alcohol abuse. He has been arrested a number of times over the years for illegal activities which he stated that he engaged in [sic] order to support his drug and alcohol habits.”
In ruling upon the State’s motion to dismiss the amended petition without an evidentiary hearing, the circuit court, having examined the petition and exhibits, remarked as follows:
"We have had an opportunity on several occasions, I might add, to review all of the material that has been submitted to us. Obviously, we are very familiar with the case, having heard the case, the case at the trial level, and having presided over all of the proceedings therein, not only on the trial but also the preliminary motions, and also obviously the sentencing proceedings. We have reviewed the post-conviction petition. ***
*** We *** feel, and we have reviewed this thoroughly, that the provisions, the two-pronged test in Strickland; i.e., whether counsel’s performance at the sentencing proceeding fell below what is commonly accepted standard and maybe more importantly at least in the Court’s mind, but for that error, whether the results would be different, and we most respectfully come down on the side of the State because we feel it would not have, and the motion to dismiss the post-conviction petition will be granted.”
Available to the trial judge prior to sentencing was the presentence investigation report, to which defendant refers in his amended petition. About the physical and mental health of the defendant, who was born in November of 1966, the report says,
"The defendant states that when he was in third grade his teacher recommended he see a psychiatrist. He states he saw some doctor for his third and fourth grade years once a week. He states he has no idea' why he was seeing this doctor and doesn’t remember what the doctors [sic] name was.
The defendant states that since fifth grade he was placed in slow learner classes and does not have any idea why he was placed in that type of program.”
Of defendant’s history of alcohol and drug use, the report indicates,
"The defendant states he began drinking at age seventeen and stated since that time he has been drinking beer and/or vodka every day, depending on the day he may drink anywhere from three beers to a twelve pack and/or one half pint vodka.
The defendant states he began using marijuana at age seventeen. He also states he uses marijuana and cocaine everyday and has so since around age seventeen.
He states he smokes two nickel bags of marijuana everyday and states he uses $20.00 to $25.00 a day of cocaine. He states he supported his habits by Public Assistance, odd jobs, paper routes, and his mother. The defendant states he knew he had a drug problem since age seventeen but has never tried to get help for this problem.”
It is well established that the standard for determining whether a defendant has received effective assistance of counsel at trial or at a death penalty hearing consists of two elements, deficiency and prejudice. People v. Brisbon, 164 Ill. 2d 236, 245-46 (1995); Strickland v. Washington, 466 U.S. 668, 80 L. Ed. 2d 674, 104 S. Ct. 2052 (1984) (adopted by this court in People v. Albanese, 104 Ill. 2d 504 (1984)). Under this two-part test, a defendant must show that counsel’s performance fell below an objective standard of reasonableness and that there is a reasonable probability that, were it not for counsel’s professional errors, the result of the proceeding would have been different. Whitehead, 169 Ill. 2d at 390. A reasonable probability is one sufficient to undermine confidence in the outcome of the proceeding. Whitehead, 169 Ill. 2d at 390. To establish ineffective assistance of counsel at a death sentencing hearing, the defendant must prove that counsel’s representation was deficient and that, but for counsel’s deficient conduct, the sentencer would, have concluded that the balance of aggravating and mitigating factors did not warrant death. Brisbon, 164 Ill. 2d at 246.
We need not determine whether counsel’s performance fell below an objective standard of reasonableness because defendant fails to show that counsel’s alleged omissions prejudiced him. The gulf is relatively slight between what the trial judge knew from his reading of the presentence investigation report at the time of sentencing with respect to defendant’s intellectual and developmental deficits and his drug and alcohol abuse and what defendant alleges in this regard in his amended post-conviction petition. As a result, there is no reasonable probability that, had counsel provided this information to the court and focused upon it at the sentencing hearing, the court would have concluded that the balance of aggravating and mitigating factors, which are summarized in the opinion in defendant’s direct appeal, did not warrant the imposition of the death penalty. Indeed, the circuit court, which noted that it had reviewed all of the material submitted with respect to defendant’s amended post-conviction petition and that it had presided over all of the proceedings related to defendant’s trial and sentencing hearing, ruled in favor of the State because of the court’s express feeling that the outcome would have been no different. Our reading of the record leads us to the same conclusion. This entirely reasonable determination by the circuit court can hardly be said to be manifestly erroneous, and we will not disturb it.
Defendant contends next that he was denied the effective assistance of counsel at sentencing because trial counsel advised him "that the court would not impose death, and [defendant] relied upon that advice when he waived jury.” He claims that he was induced to waive jury for sentencing through trial counsel’s assurance that the judge had signaled that he would not sentence defendant to death. In an affidavit attached as an exhibit to his amended petition, defendant states, "[Bjefore the time that I waived my right to a jury at sentencing, my trial counsel, Clare Hillyard, advised me that the trial judge *** had stated to her that [he] would not impose the death penalty if I waived a jury at sentencing.” Defendant states further, "[I]n reliance upon counsel’s advice that Judge Karnezis would not impose the death penalty, I agreed to waive a jury at sentencing, despite my initial reluctance to waive my right to a jury.” In an affidavit attached as an exhibit to defendant’s amended petition, Clare Hillyard, who was one of defendant’s trial attorneys, states as follows:
"That [defendant] agreed to waive a jury for any possible sentencing proceedings prior to the jury selection in the guilt-innocence phase of his trial; that he was fully informed of the advantages and disadvantages of his options; that careful consideration was given to this decision over a long period of time.
*** That during a strategy discussion after the jury verdict, the Judge made a comment in the presence of the State’s Attorneys, defense counsel and the defendant about the death penalty, 'if it comes to that’; [t]hat a facial expression and voice inflection inspired the belief that the death penalty would not be imposed; that none of the prepared mitigation was curtailed as a result of said comment.”
Also attached to the amended petition as an exhibit is the affidavit of Charles Hoffman, who represented defendant in his direct appeal; he states that at a meeting following defendant’s conviction and sentencing, Clare Hillyard and defendant’s other attorney at trial, Michael Brennock, told him that
"prior to sentencing, they had firmly believed that Judge Karnezis would not impose death on [the defendant]. They said they got what they interpreted as a 'signal’ from Judge Karnezis that if they took a bench sentencing, he would not impose a sentence of death. Brennock said that in his discussions with [defendant] on whether to take a bench or jury sentencing, Brennock told [defendant] that he was '99% sure’ that Judge Karnezis would not impose death. Hillyard and Brennock told me they were 'stunned’ when Judge Karnezis imposed death on [defendant].”
Another affidavit attached to defendant’s amended petition as an exhibit is tipiat of David Rothal, who is one of the attorneys representing defendant in this appeal. He indicates that during a three-way telephone conference with Clare Hillyard and the other attorney representing defendant in this appeal, "Ms. Hillyard stated that based upon Judge Karnezis’ statement 'if it comes to that’, her determination that [defendant’s] case was not a particularly aggravating one, and other factors, she recommended to [defendant] that he waive a jury for sentencing.”
In defendant’s direct appeal he contended that his waiver of a jury for purposes of the sentencing hearing was invalid because it was based on the erroneous advice of his attorney, given to him because of counsel’s mistaken belief that evidence of defendant’s involvement in offenses of which he had not yet been convicted could not be introduced at the sentencing hearing. Maxwell, 148 Ill. 2d at 140, 143. Defendant maintained that counsel was ineffective and his jury waiver, therefore, invalid. Maxwell, 148 Ill. 2d at 142. Counsel’s error notwithstanding, this court concluded, on the record before it, that counsel had not rendered ineffective assistance in advising defendant to waive a jury and that the defendant’s jury waiver was not invalid on this ground:
"As an examination of defense counsel’s remarks makes clear, counsel offered three distinct reasons in support of her decision to advise the defendant to waive a jury for the sentencing hearing. First, counsel apparently believed that the judge was more likely to be lenient than a jury; counsel stated that she and her client preferred that the judge make the sentencing determination. Second, counsel wanted to preclude death-qualification of the jury for purposes of the guilt phase of the proceedings. (See Daley v. Hett (1986), 113 Ill. 2d 75.) Third, counsel did not want the sentencing decision to be made by a jury if its members had been exposed to, or, in counsel’s words, had been 'inflamed’ by, evidence of the defendant’s other offenses. For these reasons, then, counsel recommended that the defendant waive a jury for the death penalty hearing.
'A convicted defendant making a claim of ineffective assistance must identify the acts or omissions of counsel that are alleged not to have been the result of reasonable professional judgment.’ (Strickland, 466 U.S. at 690, 80 L. Ed. 2d at 695, 104 S. Ct. at 2066.) Any one of the three grounds mentioned by counsel constitutes a valid reason for choosing to waive a sentencing jury.” Maxwell, 148 Ill. 2d at 143-44.
Under the circumstances, this court said, counsel’s mistaken belief concerning the admissibility of evidence of other crimes did not result in an act or omission reflecting unreasonable professional judgment; counsel’s recommendation that the defendant waive a jury for the sentencing phase was entirely consistent with counsel’s strategy to avoid submitting the sentencing determination to jurors who were aware of the defendant’s criminal record. Maxwell, 148 Ill. 2d at 144.
In defendant’s direct appeal the court’s conclusion that defendant had failed to show that counsel had acted in a professionally unreasonable manner was dispositive of the defendant’s claim for failure to establish one of the two necessary parts of the Strickland test. However, this court went on to consider whether, assuming that counsel’s mistaken belief resulted in a professionally unreasonable act or omission, defendant sustained prejudice as a consequence. The court determined that he had not, concluding that defense counsel would have offered the same recommendation had she known that the evidence of the defendant’s other crimes would later be admissible at the sentencing hearing. Maxwell, 148 Ill. 2d at 145. The court pointed out,
"As we have stated, one reason for counsel’s recommendation to the defendant that he forgo a jury for sentencing was to avoid submitting the sentencing determination to jurors who were aware of the defendant’s extensive criminal record. Recognition that the jurors would eventually acquire this information at the sentencing hearing could only have confirmed counsel in her assessment that a jury waiver was necessary to effectuate her strategy. Here, counsel achieved her avowed goal of not having the sentencing determination submitted to a jury if its members were aware of the defendant’s criminal history.” Maxwell, 148 Ill. 2d at 145-46.
In effect, defendant attacks in his post-conviction petition one of the three grounds stated by counsel as a reason for choosing to waive a jury for sentencing, namely, counsel’s belief that the judge was more likely to be lenient than a jury. However, two valid reasons remain for defendant’s having chosen to waive a jury at sentencing: the wish to preclude death-qualification of the jury for purposes of the guilt phase of the proceedings and the desire to avoid sentencing by jurors who had been exposed to evidence of defendant’s other offenses. Thus defendant could have suffered no prejudice as a result of counsel’s advice to waive a jury for sentencing. Inasmuch as defendant cannot meet the requirement of Strickland that he show prejudice, namely, that he would not have waived his right to a jury in the absence of the error alleged (see Maxwell, 148 Ill. 2d at 142), the circuit court properly dismissed this claim of his amended post-conviction petition without an evidentiary hearing.
In the third issue defendant presents for our review, he contends that he was denied his constitutional rights as a consequence of the proceedings in which he waived a jury for sentencing. More specifically, he maintains that he was denied due process because the trial court did not ask him whether any promises were employed to induce his waiver, which was obtained, he avers, as the result of a misrepresentation by counsel that such a promise had been made. Despite the different origins of a defendant’s right to a jury at the guilt phase of the proceedings and his right to a jury at the capital sentencing hearing, the waiver of either right to a jury must be knowing, intelligent, and voluntary. People v. Strickland, 154 Ill. 2d 489, 517 (1992). As defendant points out, this court held in People v. Albanese, 104 Ill. 2d 504, 535 (1984), the sixth amendment requires no precise formula for determining whether a waiver has been knowingly and intelligently made. The court need not deliver a formulaic recitation prior to receiving a defendant’s valid waiver of a jury at a capital sentencing hearing. Strickland, 154 Ill. 2d at 517. Instead, each case turns on its own facts and circumstances. Albanese, 104 Ill. 2d at 535-36.
With respect to the defendant’s waiver of a jury for sentencing, the record includes the following colloquy between the trial court and the defendant:
"THE COURT: Okay, Mr. Maxwell, your attorney is indicating at this time that in the event, in the event that the jury were to find you guilty of the charge of murder, and in the further event that the State indicated that they would be seeking the death penalty, it would be your • intention to waive your right to have that jury determine that question. Do you understand what I am saying?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: Okay. Now, you have a right to have a — jury decide the question of whether or not the death penalty is to be imposed. Do you understand?
DEFENDANT MAXWELL: (Nodding head.)
THE COURT: Now, that, of course, would only arise if in the event you were found guilty of the offense of murder. Do you understand that?
DEFENDANT MAXWELL: Yes.
THE COURT: Now, that right cannot be taken away from you. You must knowingly waive or give up that right to have the jury make that determination. Do you understand that?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: If you waive that right, the right to have a jury make that determination, I will hear the — it would be up for — it would be for me to determine whether the death penalty would be imposed or not in the event that you were found guilty. Do you understand that?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: ***
What I am saying, instead of having 12 jurors reach a unanimous verdict of 12 to nothing, it would be for me alone to make that decision. Do you understand that?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: Now, do you wish a jury to make that determination, or do you wish to have a judge, myself, decide that — make that decision in the event that you are found guilty?
DEFENDANT MAXWELL: You, sir.
THE COURT: You wish to have me make that decision?
DEFENDANT MAXWELL: Yes, sir.
* * *
THE COURT: ***
When we say, Mr. Maxwell, that the 12 people must decide, there could be a situation where 11 people say the death penalty should be imposed and one says it should not, and the death penalty would not be imposed. You understand thát, that that decision by the 12 jurors must be a unanimous decision, and in the event that it is not a unanimous decision, then the death penalty could not be imposed. Do you understand that?
DEFENDANT MAXWELL: (Nodding head.)
THE COURT: And knowing and understanding all of these things which I have just stated, you are choosing to waive your right to a jury for the penalty phase, is that correct?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: *** I will ask you to indicate that by signing the waiver which your attorney has prepared. I just want to make sure that we are covering all of the points.
Now, Mr. Maxwell, you are making this waiver. You have executed this waiver freely and voluntarily?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: Nobody has threatened you in any way?
DEFENDANT MAXWELL: No, sir.
THE COURT: Nobody is forcing you to sign this waiver, is that correct?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: And I assume you have discussed this matter with your attorneys prior to today, have you not?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: Okay, and after discussing it with them, you are choosing at this time to waive your right to have a jury make the determination as to whether the death penalty should be imposed in the event there is a finding of guilty?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: That is your wish?
DEFENDANT MAXWELL: Yes, sir.
THE COURT: Okay, I believe I have covered, I hope, all of the possible — just give me one more second.
Okay, we will in our discretion accept that jury waiver, and that will be made a part of the file.”
As the State indicates, the inquiry by the trial court was extensive and thorough, exploring fully defendant’s understanding of that which he was relinquishing. We agree with the State that while this colloquy does not include an inquiry as to whether any promises were made, it establishes sufficiently the knowing, intelligent, and voluntary nature of defendant’s waiver of a jury for sentencing. We conclude that defendant was not denied due process in this regard and that his waiver was effective. Hence, the circuit court appropriately dismissed the third claim of defendant’s amended post-conviction petition.
In another issue defendant raises for review, he contends that his constitutional rights were violated "at the pre-trial motions stage of the trial, because studies and reports, establishing that physical abuse of prisoners and coercion of confessions at Area 2 Violent Crimes was widespread and systematic — evidence which would have been instrumental in persuading the court to grant defendant’s motion to suppress evidence — were not available to the defense at the time of trial.” Defendant argues that the physical abuse and denial of rights that were employed to obtain his confession were found to be a regular practice at Area 2 Violent Crimes, where hé gave statements confessing his involvement in the offenses in question. In his amended post-conviction petition, he alleges that had this evidence been available to counsel at the time of his trial, it could have served as the basis for admitting specific evidence from other victims of abuse to rebut the mere denials of police that they beat defendant and refused to allow him to call his lawyer. He alleges further that had the trial court "been informed of the extent of abuses occurring at Area 2, of the sanctioning of these abuses — and participation in them — by command, and the evidence that officers who conducted [defendant’s] interrogation were specifically named among the perpetrators [Ex. 19, 22, 25, 26, 27, 53, 56], it is reasonable to conclude that defendant’s motion to suppress confession would have been granted.” As a consequence, he alleges, the outcome of his trial would have been different. By "command,” defendant refers to Commander John Burge. Numerous exhibits, including affidavits, reports, and transcripts, are attached to his amended petition in support of this claim.
In ruling on the motion of the defendant as well as those of his two codefendants to suppress statements, the trial court expressly found "that they were not struck or threatened in any way by Detective Paladino, Detective Glynn, Detective Basile, and Assistant State’s Attorney Telander.” In so ruling, the trial court found further "no evidence of physical abuse” and that "[a]ny alleged injury to any of these individuals did not occur as a result, Court finds did not occur as a result of any police action prior to these statements being made.” In support of his motion to suppress the oral and signed statements that he had given on November 12, 1986, defendant had introduced into evidence photographs taken a week later, on November 19,1986. The defendant testified at the hearing on his motion to suppress statements that the pictures showed a knot on the left side of his head, swelling above his eyebrow, and a knot on his right leg.
When it is evident that a defendant has been injured while in police custody, the State must show by clear and convincing evidence that the injuries were not inflicted as a means of producing the confession. People v. Wilson, 116 Ill. 2d 29, 40 (1987). To do so requires more by the State’s witnesses than mere denial that the confession was coerced. Wilson, 116 Ill. 2d at 40. Here, however, it was not evident that the defendant had been injured while in police custody. In view of the trial court’s findings that there was no evidence of physical abuse óf the defendant and that any alleged injury did not occur as a result of any police action prior to giving the statements sought to be suppressed, the defendant, by these tangential allegations, has failed to make a substantial showing that his constitutional rights were violated. Thus, the determination of the trial court dismissing his amended post-conviction petition without an evidentiary hearing was not manifestly erroneous, and we do not disturb it.
In another, related issue defendant asserts that he was denied his right to due process when the State failed to disclose to the defense that the deprivations of rights complained of in his motion to suppress statements were widespread and systematic at Area 2 Violent Crimes Headquarters. In his amended post-conviction petition, he alleges that prior to trial he filed, a motion for discovery requesting that the State produce "any and all material or information within its possession or control which tends to negate the guilt of the accused as to the offense charged or would tend to reduce his punishment therefor.” In its answer to discovery the State responded, "None known to the. People.” In his brief defendant states that the superintendent of police failed to notify the State’s Attorney and the judiciary that an internal investigation revealed that Area 2 had become the scene of widespread abuses. While, defendant considers it "doubtful that the specific prosecutors whose answer to discovery misled the defense in this case were actually aware that reports existed which would gravely undermine the credibility of the police,” he maintains that prosecutors had a duty under Brady v. Maryland, 373 U.S. 83, 10 L. Ed. 2d 215, 83 S. Ct. 1194 (1963), to tender this information to defense counsel pursuant to defendant’s motion for discovery. He argues that evidence of the abuses and beating that were practiced at Area 2 Violent Crimés and by the detectives who interrogated deféndant would have tended to negate his guilt because such evidence would have increased the likelihood that his coerced statement would have been suppressed. Even assuming that suppression of the defendant’s inculpatory statements to police would have led to his acquittal, in light pf the findings of the trial court following the hearing on his motion to suppress these statements, particularly the court’s finding of "no physical abuse” of the defendant, he has failed to make the requisite substantial showing that his constitutional rights have been violated.
Ten of the issues defendant asks us to consider were raised in his direct appeal. He merely, repeats them here without argument, stating that he stands on the arguments set forth in his brief in the direct appeal, which is included in the record as an exhibit attached to the amended post-conviction petition. The scope of post-conviction review is limited by the doctrines of both res judicata and waiver, with the result that post-conviction proceedings are limited to issues that have not and could not have been previously adjudicated. People v. Stewart, 123 Ill. 2d 368 (1988). All issues actually decided on direct appeal are res judicata, and all those that could have been presented but were not are deemed waived. Stewart, 123 Ill. 2d at 372. These ten issues raised in his direct appeal are res judicata, and we do not address them further.
We have read the entire record for review and have examined it with regard to the remaining issues defendant presents. We conclude that they are without merit.
Therefore, for the reasons stated above, we affirm the judgment of the circuit court of Cook County dismissing the defendant’s amended petition for post-conviction relief. We hereby direct the clerk of this court to enter an order setting Wednesday, November 13, 1996, as the date on which the sentence of death entered by the circuit court of Cook County is to be carried out. The defendant shall be executed in a manner provided by law (725 ILCS 5/119 — 5 (West 1994)). The clerk of this court shall send a certified copy of the mandate in this case to the Director of Corrections, to the warden of Stateville Correctional Center, and to the warden of the institution where defendant is now confined.
Affirmed.