Johnnie L. Cole was tried and convicted of second-degree murder. CL 1948 § 750-.317 (Stat Ann 1954 Rev § 28.549). He was sentenced for 35 to 50 years and now appeals.
Factually, the case involves another senseless homicide. Cole was awakened one morning and told that a man from the Consumers Power Company was shutting off the electric power to the Cole home. Cole dressed, picked up his revolver, and went out to talk to the Consumers Power man. After a brief conversation, Cole raised his gun and shot the man several times. Cole then went back into his house and either called the sheriff himself or had some one in his family make the call and reported the killing. Sheriff’s deputies who responded to the call testified that Cole was cooperative and related what had occurred in an even, unemotional manner.
Cole had no prior criminal record. His standing in the community was very good and he was very active in church functions and religious fraternal organizations. He did have a record of mental illness; he had been honorably discharged from the *254armed services for psychiatric reasons and was receiving a veteran’s administration disability pension. Cole underwent periodic psychiatric checkups in connection with his YA pension and had received such an examination 4 days prior to the shooting. The examining psychiatrist concluded that Cole was then in a state of moderate remission from his previous schizophrenic reactions but that he might act irrationally under stress. At trial, the defense produced two additional expert witnesses who testified that Cole had psychiatric disabilities. Cole’s main defense was insanity. The testimony of the three expert witnesses raised the insanity question squarely for jury consideration.
Appellant Cole raises several questions on appeal. The first of these involves some 17 questions which defense counsel proposed for the voir dire examination. The court refused to propound 12 of these questions to the prospective jurors. By the provisions of GCB. 1963, 511.3 the examination of prospective jurors may be conducted by the court or the attorneys. Further, a “large discretion is vested in the trial court as to the scope of examination of jurors on their voir dire.” People v. Rose (1934), 268 Mich 529, 531. The purpose of the voir dire examination is to enable the attorneys to elicit such information as to develop a rational basis for the exercise of challenges for cause or peremptory challenges. 2 Honigman & Hawkins, Michigan Court Buies Annotated (2d ed), p 465. The questions asked of the prospective jurors by the court enabled defense counsel to develop an adequate basis for the exercise of challenges.
Basically, the 17 questions submitted to the court by defense counsel were designed to derive four types of information from the prospective jurors. The most vital of these groupings was' designed to elicit information as to whether any of the jurors *255was predisposed against the defense of insanity and further, whether there was distrust of psychiatric testimony. The court, however, did question the jurors as to whether any of them had any bias against the defense of insanity. Another grouping of proposed questions sought to elicit what verdict they would return if there was any doubt as to Cole’s sanity. This the jurors were asked by the court. Further, defense counsel sought to question the prospective jurors as to what effect testimony concerning Cole’s reputation would have on them. The court’s refusal to ask this question was not reversible error. Finally, counsel requested that the jurors be asked what their verdict would be if the evidence were equally balanced. Refusal by a court to ask this question is not error unless some' prejudice is shown to have resulted. People v. Lockhart (1955), 342 Mich 595; People v. Allen (1958), 351 Mich 535. Cole has made no showing of prejudice. Further, the jurors were asked whether they would follow the usual presumptions, which presumptions would encompass the answer to the proposed question. "We find no reversible error in the voir dire examination.
Counsel for appellant questions whether there was sufficient evidence before the jury to find the appellant guilty beyond a reasonable doubt. The main point of appellant’s evidentiary argument seems to be that the people introduced ho expert testimony to rebut the psychiatric testimony offered' in Cole’s defense. Since sanity is the normal human condition, a defendant is presumptively sane until some contrary evidence is introduced to rebut this presumption. When, however, evidence is introduced which raises the sanity issue, the burden of proof shifts to the prosecution to prove the defendant was sane beyond a reasonable doubt. People v. Garbutt (1868), 17 Mich 9. It does not *256follow, however, that sanity must be proved by expert witnesses or that expert opinions must be rebutted by expert testimony. See Vial v. Vial (1963), 369 Mich 534, 536. In the record before us, there is testimony from which the jury could find that the appellant was sane at the time the homicide was committed. This being the case, the expert opinion evidence introduced by the defense was not controlling. People v. Krugman (1966), 377 Mich 559. The question of Cole’s sanity was a disputed fact question for the jury to decide and we cannot say their finding in this regard was without factual support.
Defense counsel requested the trial court to charge the jurors on the defense of insanity in accord with the Durham rule (Durham v. United States [CA DC, 1954], 94 App DC 228 [214 F2d 862, 45 ALB.2d 1430]), whereby an accused is not criminally responsible if his unlawful act is the product of a mental disease or defect. Whatever may be. the appeal of the Durham test of legal insanity, we feel constrained to uphold the long-settled Michigan tests. The charge given the jury was in accord with that approved in People v. Durfee (1886), 62 Mich 487, 493:
“If, by reason of disease, the defendant was not capable of knowing he was doing wrong in the particular act, or if he had not the power to resist the impulse to do the act by reason of disease or insanity, that would be an unsound mind;”
thus, a mind not criminally responsible. We may speculate' that the Supreme Court may some day adopt the Durham rule or return to the “incapability of criminal intent” test set out in People v. Garbutt (1868), 17 Mich 9. See People v. Krugman (1966), 377 Mich 559. However, we are not free to act on *257this speculation and alter the long approved Durfee test.
The final issue raised on appeal revolves around the question of whether the jury should have been informed of the disposition of the defendant if he was found not guilty, by reason of insanity. The statute, CL 1948 § 766.15c (Stat Ann 1954 Eev § 28.933[3]), provides in part:
“Any person, who is tried for the crime of murder and is acquitted by the court or jury by reason of insanity, shall forthwith be committed by order of said court to a State hospital for the criminally insane for the remainder of his natural life.”
Defense counsel requested that he be allowed to state the law in his argument to the jury and further requested that the jury be instructed in accord with the provisions of the law. Both requests were denied. The jurors, after a period of deliberation, submitted a question to the court seeking instruction on the disposition of the defendant if found not guilty by reason of insanity. The court informed the jury that it could not answer the question.
We find no reversible error in this part of the case. Michigan is firmly committed to the position that the jury’s duty is to determine the truth from the evidence presented and to communicate their determination to the court in the form of a verdict. Post-verdict consequences should not enter into the jurors’ deliberations.' People v. Warner (1939), 289 Mich 516. Jurors are not informed of the possible punishment that may be meted out by the court upon the return of a guilty verdict. The reason for this prohibition is that the jury’s sole *258function is to determine the truth, and consideration of the consequences of their verdict can only-hamper and confuse their deliberations. This rationale ■ applies with equal force to the present case. Knowledge of the post-verdict disposition of the defendant Cole, if found not guilty by reason of insanity, could not have aided the jury in determining whether Cole was insane or not at the time the homicide was committed. The court’s refusal either to instruct on this point or to allow counsel to state it in argument was not reversible error.
Affirmed.
J. H. G-illis, J., concurred with McGregor, J.