delivered the opinion of the court:
Defendant, Kenneth Allen, was charged by information in the circuit court of Cook County with the murder of two Chicago police officers. Following a fitness hearing, at which a jury found him competent to stand trial, defendant, pro se, pleaded guilty. Pursuant to section 9— 1(d) of the Criminal Code of 1961, the State requested a sentencing hearing to consider whether the death penalty should be imposed. (Ill. Rev. Stat. 1977, ch. 38, par. 9 — 1(d).) At this hearing, defendant again proceeded pro *26 se and also waived his right to a jury determination of the issue. The trial court found that the necessary aggravating factors existed and that there were no mitigating circumstances sufficient to preclude imposition of the death penalty. Defendant was sentenced to death. (See Ill. Rev. Stat. 1977, ch. 38, par. 9 — 1(c).) A direct appeal to this court followed. Ill. Const. 1970, art. VI, sec. 4(b); 73 Ill. 2d R. 603.
The record reveals that on December 13, 1978, Bianca Smith summoned the police to a residence where she and defendant lived. Smith told police that she needed assistance and that defendant was armed. When police arrived, defendant displayed a rifle and demanded that they remove themselves from his property. Lieutenant Robert Hanley and Commander James B. Delaney attempted to calm the defendant, and after approximately 19 hours he surrendered. Defendant was then arrested and charged with aggravated assault and misdemeanor firearm violations.
The next day, while still in police custody, defendant’s residence was searched pursuant to a warrant. The police confiscated seven firearms, along with over 1,000 rounds of ammunition. When defendant returned home, he discovered that the weapons were taken by the police and apparently became determined to seek revenge on the individuals responsible for the issuance and execution of the search warrant.
On March 3, 1979, defendant visited a locksmith and glazier shop. After asking some unusual questions of the shop’s proprietor, defendant discovered that a .45-caliber bullet would not penetrate bullet proof glass, but that police ears were not equipped with such glass. Later that day, defendant observed police officers William Bosak and Roger Van Schaik as they effected a routine traffic stop. He parked his car next to the unoccupied police car, opened fire, and fatally wounded Bosak. Defendant *27continued his attack upon Van Schaik, who returned the fire. When Van Schaik ran out of ammunition, defendant went to his car and retrieved a rifle. He fired at Van Schaik three times before the rifle malfunctioned. When the officer fell wounded, defendant took the service revolver from the body of Bosak and shot Van Schaik twice in the head at point-blank range, killing him instantly.
As other officers arrived on the scene, defendant returned to his car and sped away. After an extensive police chase, defendant was captured and arrested. A search of defendant’s car revealed three firearms and a notebook. The notebook contained the names, addresses and vehicle license plate numbers of the judge, the investigator, and police officers who were involved in the December 14,1978, search warrant.
Private counsel, Thomas Holum, was initially retained to represent defendant. However, due to defendant’s indigency, he withdrew and public defenders Stuart Nudelman and Dale Coventry were appointed. Their motion, that defendant be taken to Cermak Hospital for observation and a behavorial clinic examination, was denied.
Private counsel JoAnne Wolfson and James Cutrone were later retained to represent defendant and the public defenders were allowed to withdraw. At arraignment, Wolfson and Cutrone appeared for defendant and entered a plea of not guilty. A week later, they moved that defendant be examined neurologically and psychologically, including a brain scan and an electroencephalogram (EEC). The court granted the motion; however, defendant refused to undergo the testing. Wolfson and Cutrone moved to withdraw, stating that they deemed the tests to be an integral part of the defense. The court granted the withdrawal and allowed defendant time to seek counsel. Nudelman was appointed during the interim.
*28On August 2, 1979, public defender Richard Kling appeared for defendant and informed the court that Nudelman was ill. At that time, defendant requested an interview with a lawyer from both the Chicago and Cook County bar associations. The court allowed the request and advised defendant that if he did not want the first attorney interviewed he could interview a second, but that he should not expect that he would be permitted to go through the entire Illinois bar. The court appointed bar association attorney Cornelius Toole after finding he was acceptable to defendant.
On September 21, 1979, the State announced that it was ready for trial. Toole reported that defendant wished to be tried first on the misdemeanor firearm charges. The State then dismissed those charges, and the murder case was continued on defendant’s motion. On October 31, 1979, defendant moved to dismiss Toole, stating that he was angry because Toole “allowed” the misdemeanor charges to be dismissed. Without Toole’s foreknowledge, defendant then moved to withdraw his plea of not guilty and enter a plea of guilty. The court refused defendant’s requests and continued the case.
In November 1979, Toole informed the court that he had serious doubt regarding defendant’s fitness to stand trial. Toole’s motion for a behavorial clinic examination of defendant was granted. On November 21, the State reported that Dr. Gerson Kaplan, a psychiatrist, had examined defendant on November 20 and found him unfit to stand trial. The court then granted Toole’s request for a hearing to determine defendant’s fitness to stand trial. Defendant repeatedly objected to any proceedings regarding his fitness and refused to speak with Toole. Defendant insisted that the court accept his plea of guilty. The court, however, informed defendant that the plea would not be accepted until his fitness was determined. The court suggested to Toole that he should have *29one of his associates conduct the fitness hearing since he might be called to testify.
On November 27, 1979, William O’Neal, an associate of Toole, appeared for defendant at the fitness hearing. Defendant objected to O’Neal’s representation because of his association with Toole. Defendant’s motions to proceed either pro se or in absentia were denied. Defendant then moved that the public defender be appointed. The court allowed O’Neal to withdraw and appointed public defenders Mariam Burke and Edward Ptacek. After a jury was selected, the fitness hearing commenced.
The State called Dr. Werner Tuteur, a psychiatrist, who testified that he examined defendant at the Cook County jail on November 22, 1979. Dr. Tuteur stated that defendant knew the charges pending against him and “discovered no mental condition which would prevent the defendant from assisting in his defense.” Based upon the examination, it was Dr. Tuteur’s opinion that defendant was fit for trial.
Correctional Officer Morris testified that on November 20, 1979, defendant locked himself in his cell and had to be forcibly taken to Dr. Kaplan’s office for a psychological examination. Following this testimony, the State rested.
Dr. Kaplan was called as a court’s witness. He testified that he examined defendant and determined that defendant was unfit to stand trial because he was unable to assist in his own defense due to a “paranoid state.” Dr. Kaplan acknowledged that the examination was not conducted under optimum conditions because defendant had to be forcibly taken to his office.
A defense motion for a directed finding of unfitness was denied. The defense then presented public defenders Kling and Nudelman, who stated that, based upon their interaction with defendant, it was their opinion that *30defendant was unable to cooperate with counsel in his own defense. Over defense counsel objection, defendant testified on his own behalf. He urged the jury to consider his conduct during the proceedings and to consider the “very credible” testimony of Dr. Tuteur. Defendant also stated that he was “fit to stand trial” and was “innocent of the charge of insanity.” Closing arguments were made and both sides rested. The jury found that defendant was fit to stand trial. Attorneys Burke and Ptacek were allowed to withdraw and Toole resumed representation of defendant.
On December 3, 1979, defendant moved that Toole be discharged and that he be permitted to proceed pro se. The court advised defendant that self-representation in a murder case would be unwise. Defendant agreed and requested appointment of counsel other than Toole. The court informed defendant that another attorney would not be appointed. Thereafter, defendant persisted in his request to proceed pro se. The court, with Toole present, admonished defendant in accordance with Supreme Court Rule 401 (73 Ill. 2d R. 401) and, after it determined that the waiver of counsel was knowingly, intelligently, and voluntarily made, allowed dismissal of Toole. The court, however, requested that Toole stand by and advise defendant. Defendant then informed the court that he wished to plead guilty to both charges of murder. The court fully complied with Supreme Court Rule 402 (73 Ill. 2d R. 402) and accepted the plea after determining that there was a factual basis for the plea and the plea was voluntary.
The State requested that a sentencing hearing be held to consider whether the death penalty should be imposed. Defendant proceeded pro se and waived his right to a jury at that hearing. Defendant acknowledged that he shot two police officers with the intent to kill them. He indicated that he shot the officers because he thought *31they were involved with the “police raid” at his house on December 13, 1978. He also stated that he was “in total agreement with the State in reference to imposing the death sentence.” The court found that the State proved two statutory aggravating factors and that defendant was eligible for the death penalty. See Ill. Rev. Stat. 1977, ch. 38, pars. 9-l(b)(l), (b)(3).
In the mitigation phase of the sentencing hearing, defendant offered no evidence. The State presented several witnesses who related the events of December 13, 1978, and December 14, 1978. In closing arguments, both the State and the defendant, pro se, recommended the death penalty. Finding no mitigating circumstances sufficient to preclude the death penalty, the court sentenced the defendant to death. See Ill. Rev. Stat. 1977, ch. 38, par. 9 — 1(c).
On February 19, 1980, Deputy State Appellate Defender Ralph Ruebner informed this court that defendant did not wish to appeal his conviction or sentence. Instead, defendant desired that his execution take place on the date set by the trial court. On March 13, 1980, this court entered the following order:
“It has come to the attention of this court that Kenneth Allen, a person who has been sentenced to death by the circuit court of Cook County following his plea of guilty to two counts of murder, has expressed a desire that his execution take place upon the date fixed by the circuit court. He has purportedly stated that he does not wish to appeal his conviction and sentence. An appeal from a conviction and sentence of death is automatic, without the necessity of any action by the defendant or his counsel. Ill. Rev. Stat. 1977, ch. 38, par. 9-l(i); 73 Ill. 2d R. 606(a).
On the court’s own motion, the State Appellate Defender is appointed counsel for defendant for the purpose of an appeal of the conviction and sentence. The circuit court of Cook County is directed to permit the late filing *32 of a, motion to withdraw the plea of guilty.” (Emphasis added.) 79 Ill. 2d 471, 472.
Ruebner appeared for the defendant in the trial court on May 2, 1980. The court granted his motion for production of medical records regarding a head injury suffered by defendant in 1972. The records revealed that a portion of defendant’s brain was removed during surgery for a depressed skull fracture. They also indicated that defendant suffered from seizures.
Thereafter, Ruebner moved to have the court appoint Dr. Kaplan to conduct clinical testing and a psychiatric examination of defendant. The motion stated that the purpose of the tests was to determine, inter alia, defendant’s present sanity and his sanity at the time of the offense. Appended to the motion was Dr. Kaplan’s affidavit in which he stated that the 1972 medical records, which he had seen for the first time on May 13, 1980, “raise a reasonable possibility that Kenneth Allen was suffering from a seizure condition” and from a “psychosis.” Based upon his personal knowledge of defendant, the facts of this case, and defendant’s medical history, it was Dr. Kaplan’s opinion that defendant was “legally insane at the time of the offense.” Dr. Kaplan also stated that psychological testing and psychiatric evaluations, including an EEG, were necessary to determine more definitely defendant’s mental condition.
The State filed answers opposing both the appointment of Dr. Kaplan and any further testing. The court appointed Dr. Kaplan but limited the scope of that appointment to psychological and psychiatric examinations of defendant at the Stateville Penitentiary. In addition, the court stated:
“Now, if, after those examinations, the facilities there do not permit some particular examination that might be necessary, I think we can make some arrangements in the vicinity there to provide for it.”
On June 24, 1980, by letter, Dr. Kaplan informed the *33court that he examined defendant and, based upon this examination, it was his opinion that the defendant was legally insane at the time of the offense due to the mental condition of “paranoid state.” Thereafter, Ruebner renewed his motion for further clinical and psychiatric examinations and requested that brain-wave tests be performed. The court then asked that Ruebner supply it with a medical opinion as to whether such tests were necessary. By letter on August 26, 1980, Dr. Kaplan informed the court and advised that there was a need for further tests. He recommended that an EEG, a brain scan and additional psychological examination be performed.
On October 15, 1980, Ruebner appeared and reiterated his position that additional tests were required. The State responded that further tests were not needed; however, it offered no evidence to support its conclusions or to rebut Dr. Kaplan’s findings or recommendation for additional testing. Although the allegations of Ruebner’s petition and supporting affidavit were uncontroverted, and contrary to its previous indication that any necessary examinations would be allowed, the court denied the motion for further testing. Ruebner then filed a motion to withdraw the plea of guilty, and that motion was also denied.
Defendant raises many issues on appeal. Because of the conclusion reached, we need address but one issue.
Defense counsel argues that the trial court erred in refusing to order additional testing to determine defendant’s sanity at the time of the offense. He made an offer of proof that the testing would establish that defendant suffered from organic brain damage and would confirm Dr. Kaplan’s diagnosis that defendant was paranoid and not legally responsible for his conduct on March 3, 1979. The State asserts that the 1972 medical records were not newly discovered and that defendant’s failure to raise the defense of insanity constituted a waiver. The State also maintains that further neurological and psychological tests *34were unnecessary because the head injury incurred by defendant in 1972 did not result in any permanent disorder. However, the State did not offer any basis in fact to support this conclusion.
Deeply rooted in our concept of liberty and due process is the requirement that an accused person must be of sound mind at the time of the perpetration of the offense, the trial, and imposition of sentence and execution. (See People v. Anderson (1964) 31 Ill. 2d 262, 264; People v. Reeves (1952), 412. Ill. 555, 561; see also People v. Lego (1965), 32 Ill. 2d 76, 78; People v. Burson (1957), 11 Ill. 2d 360, 368.) The petition for further testing and Dr. Kaplan’s supporting affidavit indicated that defendant was not of sound mind at the time of the offense due to a “paranoid state” and “psychosis.” Under Illinois law, a paranoid condition may form the basis for an insanity defense if that condition substantially impairs a defendant’s ability to refrain from wrongful conduct. People v. Moor (1934), 355 Ill. 393, 399; People v. Lowhone (1920), 292 Ill. 32, 48.
It is true that insanity, as many other defenses, is a defense to be asserted at trial, and the responsibility of raising it rests on the defendant. (People v. Reeves (1952), 412 Ill. 555, 562.) However, the failure of a defendant to raise the issue will not always preclude him from later having the question considered. As stated by the court in People v. Burson (1957), 11 Ill. 2d 360, 370-71:
“We recognize that counsel for defendant did not present or argue this point; and that the general rule is that where a question is not raised or reserved in the trial court, or where, though raised in the lower court, it is not urged or argued on appeal, it will not be considered and will be deemed to have been waived. However, this is a rule of administration and not of jurisdiction or power, and it will not operate to deprive an accused of his constitutional rights of due process. ‘The court may, as a matter of grace, in a case involving deprivation of life or liberty, take notice of errors appearing upon the *35record which deprived the accused of substantial means of enjoying a fair and impartial trial, although no exceptions were preserved or the question is imperfectly presented.’ ”
Moreover, the State’s argument ignores the purpose of the order entered by this court on March 13, 1980. That order was designed to allow the Appellate Defender an opportunity to delve into the proceedings surrounding defendant’s conviction and death sentence. Ruebner’s motion for further testing was for the purpose of complying with our order and preparing a motion to withdraw the guilty plea.
The question of defendant’s sanity at the time of the offense was first advanced by the Appellate Defender in this appeal. However, the record does show that approximately four of the nine attorneys who represented defendant tried to explore the possibility of raising the insanity defense. But, each time his counsel sought to gather evidence relating to that defense, defendant refused to allow them to do so. We note that, ordinarily, the consequences of a defendant’s refusal to cooperate with his attorney will not serve as grounds for reversal. (See People v. Myles (1981), 86 Ill. 2d 260, 270-71, citing People v. Solomon (1962), 24 Ill. 2d 586, 589-90.) However, in this case, defendant’s lack of cooperation with his attorneys imposed a substantial burden which, in effect, denied the trial court access to information relating to the factual basis for the guilty plea as well as the affirmative defense of insanity at the time of the offense. See People v. Thomas (1969), 43 Ill. 2d 328, 332.
A similar situation was before the court in Costas v. People (1956), 9 Ill. 2d 534. In that case, defendant was sentenced to 50 years’ imprisonment upon a plea of guilty to an indictment for murder. On appeal, defendant moved to have the judgment of conviction vacated because certain facts regarding his state of mind at the time of the offense were not presented to the court when judgment was entered. Both of the attorneys who were appointed to repre*36sent defendant filed sworn affidavits that defendant was not mentally competent at the time the plea of guilty was entered and that defendant insisted that they secure the death penalty for him. An offer of proof made by defense counsel indicated that a psychiatrist would testify that, although defendant was able to cooperate with counsel, he was suffering from a mental illness at the time of the offense. The court held that, because the affidavits and offer of proof stood uncontested, justice required that a hearing be held on the petition to vacate the judgment.
In the instant case, the implications raised by the petition and supporting affidavit are not contradicted by any other evidence of record upon the remand. Moreover, the facts upon which the petition and supporting affidavit are based were not known to the trial judge when he permitted defendant to withdraw his plea of not guilty and enter a plea of guilty. As in Costas, “[i]f [the allegations] are true, and the conditions they indicate had been known to the trial judge, we assume that he would have refused to accept the plea of guilty until [defendant’s] competence had been determined in the manner provided by statute.” 9 Ill. 2d 534, 538-39.
As noted above, when this court entered the order of March 13, 1980, the purpose was to allow the Appellate Defender an opportunity to gather evidence in support of the motion to withdraw the guilty plea. Euebner attempted to do so by investigating defendant’s present state of mind and his state of mind at the time of the homicides. His petition for additional tests, along with the affidavit of Dr. Kaplan, clearly raise a sufficient question concerning defendant’s sanity. The uncontested allegations of the petition and the supporting affidavit required the trial court to order further testing of defendant, as it had previously indicated that it would. We conclude, therefore, that the trial court’s refusal to do so was error.
For the above-stated reasons, and because of the unu*37sual circumstances of this case, we find that the refusal of the circuit court of Cook County to grant the petition for further testing was error. Accordingly, the order of that court is reversed and the cause is remanded with directions to allow both parties to conduct a complete psychological, psychiatric and neurological examination of defendant. Thereafter, if the allegations of the petition are proved, the judgment on the plea of guilty must be vacated and a new trial ordered. If not proved, the original judgment and sentence shall be reinstated. '
Reversed and remandad, with directions.