The opinion of the Court was delivered by
Sullivan, J.Defendant was tried by jury and convicted of armed robbery, theft of a motor vehicle, assault with intent to kill a police officer and carrying a weapon without a permit.1 He received sentences aggregating 12 to 15 years in State Prison and was fined $10,000. On appeal to the Appellate Division, his conviction was reversed on the ground that the prosecutor’s conduct and comments during trial and summation exceeded the perimeters of fair play, and prejudiced defendant’s rights to a fair trial.2 This Court granted certification. 63 N. J. 257 (1973).
The basic facts on which the criminal charges were based are not disputed by defendant, his sole contention being that he was insane at the time he committed the acts charged. This affirmative defense was presented through the testimony of a number of lay and medical witnesses. Defendant did not take the witness stand in his own behalf.
The State’s evidence showed that on September 18, 1969, Mrs. Irene Margules, while at home, was talking with a friend of hers on the telephone when her front door bell rang. She called to her housekeeper to answer the bell and then told her friend to hold on for a minute while she went to see who was at the door. Mrs. Margules put the phone down and walked over to the top of the stairs where she saw a man on *291the stairway. The man said he was from the tax department. (At trial defendant was identified by Mrs. Margales as the man in question.) After Mrs. Margules told defendant to wait downstairs, he pulled a gun out of a briefcase he was carrying, came upstairs, and demanded to know where the jewelry was. Without reciting all the details, it is enough to note that defendant, and an accomplice named Parks, took Mrs. Margules’s watch, ring and money at gun point and then used plastic tape, which they had brought with them, to tie up Mrs. Margules and her housekeeper, leaving both women on the bedroom floor.
In the meantime, Mrs. Margules’s friend, who was still holding the phone, heard enough of what was going on to realize that an armed robbery was in progress. She immediately called the police and reported what she had heard.
Lieutenant Kennedy, the first officer to arrive, entered the house, saw defendant and identified himself as a police officer. Defendant whirled around with a gun in his hand and pulled the trigger, but the gun did not fire. Defendant then ran out of the house to a car and for the second time turned and attempted to fire the gun at Kennedy who was pursuing him. Again the gun misfired.3 Kennedy then arrested defendant at gunpoint. Mrs. Margules’s watch and ring were found in defendant’s pocket. The accomplice escaped.
In an oral statement made to a police officer sometime later, defendant said that prior to the robbery he had first seen Mrs. Margules in Miami, Florida, while she was in a ticket line at the airport and noticed that she was wearing expensive jewelry. While waiting in line' he obtained Mrs. Margules’s address from one of her children who was with her and wrote it in his notebook. Defendant also said that his accomplice *292Parks was a “muscle man” he had used to collect gambling debts.4 The robbery was planned, according to defendant, because he was quite a bit in debt and while going through his notebook had come across Mrs. Margules’s name and remembered the expensive jewelry she had worn.
At trial, evidence was produced on behalf of defendant to -the effect that the DiPaglia family had several successful business enterprises, and that in September 1969 (when the Margules robbery took place) defendant’s net worth in these ventures was in excess of $360,000.
On his appeal to the Appellate Division, defendant raised some thirteen points, many of which were subdivided into numerous specifications of alleged error. We have reviewed these contentions and, without detailing each and every one of them, conclude that no reversible error has been shown as to any or all of them. We find it necessary to comment only on the trial court’s charge dealing with the defense of insanity, and the conduct and comments of the prosecutor during trial and summation which the Appellate Division found to constitute reversible error.
The trial court in charging the jury on the defense of insanity said the following:
Under our law all persons are presumed to be sane and, therefore, responsible for their conduct, unless and until the contrary is established.
Insanity is an affirmative defense, and the burden of proving it clearly by a preponderance of the evidence is on the defendant urging it as a defense. If there is no preponderance of the evidence of insanity in the case, the defense of insanity fails and the presumption of sanity is not rebutted. In such ease, the defendant stands in the position of a sane man responsible, on all of the evidence in the case, for all of his acts, whatever you may find them to have been.
*293It also charged:
The presumed sanity of a defendant is not overcome until you determine that the defendant has sustained his burden of proving by a preponderance of the evidence that at the time of the offenses alleged he was insane under the legal definition of insanity and, therefore, is absolved of responsibility for conduct for which he would otherwise be responsible under our law.
Defendant had objected to any charge of a presumption of sanity. In the alternative he requested that if the court did mention such presumption, the jury be charged that the presumption was not evidence of sanity, could not be treated as such by the jury, had no probative force, and disappeared from the case once evidence of insanity was introduced. As noted above, while the trial court did mention the presumption of sanity, it did not use the language requested by defendant.
Preliminarily, defendant argues that by the use of the word “clearly” in its charge, supra, the trial court increased the burden of proof required to sustain the defense of insanity. Ho such objection was made at trial and we find no error. In its overall ‘charge the court emphasized that defendant’s burden of proof was “by a preponderance of the evidence” which the court defined. In the portion of the charge complained of the phraseology is poor, but the meaning is quite clear. Ho increased burden of proof was imposed on defendant. See State v. Maioni, 78 N. J. L. 339, 342-343 (E. & A. 1909).
New Jersey adheres to the rule that in a criminal case ' the State does not have to prove that the defendant is sane. If insanity is raised as a defense, the defendant has the burden of proving insanity and unless he does so by a preponderance of the evidence he stands in the position of a sane person responsible in law for his actions. In discussing this principle cases refer to the presumption of sanity which must be rebutted or overcome if the defense is to prevail. State v. Cordasco, 2 N. J. 189 (1949); State v. Scelfo, 58 N. J. Super. 472 (App. Div. 1959).
*294The expression “presumption of sanity” used in these cases is not precise because we are not dealing with a true presumption in the evidentiary sense. See New Jersey Buies of Evidence, Bules 13 and 14 and Comments. All that is really meant is that a defendant asserting a defense of insanity has the burden of proving such defense. This is the context in which the cases use the expression and in which trial courts charge on the defense of insanity. It has never been understood to be a true presumption which affects the burden of going forward with proof, but rather a principle of substantive law fixing the burden of proof. McCormick, Evidence, (2d ed. 1972), § 346, p. 830. The trial court did not indicate otherwise when it charged the jury herein that “If there is no preponderance of the evidence of insanity in the case, the defense of insanity fails and the presumption of sanity is not rebutted. In such a case the defendant stands in the position of a sane man * *
In the light of the foregoing, reference to the presumption of sanity by the trial court herein was not error. However, the better practice would be not to use the expression at all. Instead, the jury should be charged that, since everyone is assumed to be sane, a defendant in a criminal case who pleads insanity as a defense, has the burden of proving such defense by a preponderance of the evidence.5
We turn to the prosecutor’s conduct and comments during trial and summation, which the Appellate Division found to exceed the perimeters of fair play and constituted reversible error. In' order to evaluate the prosecutor’s conduct some consideration must be given to the defendant’s trial tactics.
The undisputed facts surrounding the robbery indicated it was a vicious, carefully planned event. Defendant had enlisted the aid of his “muscle man,” Parks. The two men *295had come to Newark by plane, using fictitious names to purchase tickets. They registered at the Newark Airport Motel, also under assumed names. They then stole a car and proceeded to the Margules home. There the two men gained admittance to the house by a ruse, robbed Mrs. Margules at gun point and tied up the two women. When the police officer came on the scene, defendant twice attempted to shoot the officer before he was placed under arrest.
The defense was that this episode was indicative of bizarre conduct on defendant’s part which began about 1963 or 1964 and eventually resulted in his family relieving him of any business authority in 1968. As noted, there was testimony that defendant’s net worth in various family enterprises was in excess of $360,000. Defense counsel argued that since defendant was not in need of money his conduct could only be explained as a manifestation of some mental infirmity. Supporting expert medical testimony reviewed defendant’s behavior, including the incident in question, and concluded that he was a paranoid schizophrenic who on the date of the crime either did not realize that what he was doing was wrong, or if he did, was unable to appreciate the extent of the wrong.6 In his summation defense counsel characterized defendant as a person who really would not do harm to anyone and suggested that defendant knew the gun he fired at the officer was not working.
It was against this background that the prosecutor told the jury that defendant was crazy like a fox. Responding to defense counsel’s comment during summation that defendant *296would not really harm anyone, the prosecutor said “* * * we know, for example that he was a leg breaker.”7 He went on to argue that the defense of insanity was a carefully contrived fabrication to avoid defendant’s criminal responsibility. He urged the jury not to be sold a bill of goods, not to buy the Brooklyn Bridge, and let defendant get away with armed robbery because he was wealth}'. He attributed defendant’s criminal activity to his being an inveterate gambler who had incurred large monetary losses.
Within the confines of this opinion it is not practical to set forth each and every detail of the prosecutor’s conduct and comments to which objection is now made. In addition to the allegedly improper summation, defendant contends that the prosecutor, during the trial, asked unfair questions by assuming facts which he did not prove and were not true, and constantly deprecated defendant, defense counsel and defendant’s witnesses by innuendo, remarks and comment.
One incident, stressed by defendant as illustrative of the prosecutor’s alleged misconduct, involved the cross-examination of defendant’s brother on the subject of whether defendant had been barred from a golf club in Iowa for gambling. (As noted, defendant, although present in court, did not take the stand as a witness.) When defense counsel asked if the prosecutor had proof of the fact, the latter replied : “I spoke to the pro at the club yesterday.” This statement made in the presence of the jury was clearly improper and the court responded immediately by reprimanding the prosecutor and telling the jury to disregard the question and answer.
Despite counsel’s argument to the contrary, no real prejudice to defendant is shown to have resulted from the prosecutor’s improper statement. The test is whether the incident is “clearly capable of producing an unjust result.” *297R. 2:10-2. DiPaglia’s gambling proclivity was part of the defense contention that he was a schizophrenic. Dr. Colley, a defense psychiatrist, characterized defendant as a compulsive gambler. With him “gambling was absolutely supreme. Nothing else mattered.” The doctor testified that DiPaglia had told him that just prior to the robbery he had lost $20,000 in Las Vegas. On a prior occasion, defendant spent over 50 hours at the gambling tables without stopping.
In perspective, the prosecutor’s improper statement suggesting that defendant had been barred from a golf club for gambling is not shown to have been prejudicial. At most, the prosecutor should be subject to censure for his conduct.
The prosecutor comes into court as the State’s attorney. He is a constitutional officer representing the sovereign power of the people of the State by whose authority and in whose name, under the constitution, all prosecutions must be conducted. It is axiomatic therefore that in the performance of his duties he is subject to law. His presentation may be vigorous, even forceful, but it always must stay within the bounds of due process and fair play.
While we do not approve of some of the prosecutor’s actions and remarks in the matter under review, it is clear that he was attempting to meet the defense contention that defendant’s otherwise criminal conduct was but a manifestation of his insanity. The State had every right to urge upon the jury its position that defendant was legally sane.
One has to review the entire record to appreciate the flavor of the trial and how hard-fought it was on both sides. The trial court worked hard to keep the proceedings within proper bounds. Despite emotional presentations and some excesses by the defense as well as the prosecution, the issue was clear-cut and it has not been shown that the jury was misled, or defendant’s right to a fair trial prejudiced.
The judgment of the Appellate Division is reversed and the judgment of conviction hereby reinstated.
A previous trial on the same charges had ended in a hung jury.
following the reversal of his conviction, defendant was released on bail.
It was later shown that the reason the gun did not fire was that the clip containing eight bullets was not fully seated by about one-quarter of an inch, causing a lack of alignment which made it impossible for a bullet to be moved from the clip and into the firing chamber of the gun.
We were informed at oral argument that Parks, who -was apprehended subsequent to DiPaglia’s arrest, pleaded guilty to- a charge of armed robbery.
We are not disposed at this time to reconsider our previous holdings that this burden rests on and remains with defendant. State v. Cordasco, supra; State v. Scelfo, supra. However, see Proposed New Jersey Penal Code 2C :4—1, 20:4-3, 2C:1-12 (b), and Commentary.
The psychiatric opinions of defendant’s experts were based essentially on what defendant told them during interviews they had with him, as well as his behavior during the interviews. As heretofore noted, defendant did not take the witness stand. The probative value of such opinions was, of course, dependent upon whether there was independent credible proof of the verity of what defendant said and did during the interviews. State v. Lucas, 30 N. J. 37, 79-80 (1959) ; State v. Maik, 60 N. J. 203, 208 (1972) ; In re Hyett, 61 N. J. 518, 527-537 (1972).
Dr. Driscoll, a defense psychologist, had testified that defendant told him that while in military service he had broken someone’s leg in a fight over money won in a card game.