Opinion of the Court
ROBERT E. Quinn, Chief Judge:The accused, who was described as a “very outstanding” enlisted man, a “distinguished graduate” of Officer Candidate School, and the “best student” in the officer’s electronics course at Keesler Air Force Base, Mississippi, was tried and convicted for a ten-day unauthorized absence from the electronics school. He was sentenced to forfeiture of all pay and allowances and dismissal from the service. The sentence was approved by the convening authority and a board of review. We granted review to consider whether the evidence is sufficient as a matter of law to support the finding that the accused was legally sane at the time of the commission of the offense.
Before turning to the merits of the issue, it is appropriate to mark out the general limits of the evidence that we can consider. A conviction must stand or fall on the evidence admitted at trial. Recourse cannot be had to matters outside the record of trial to remove a reasonable doubt that may be left by the evidence presented at trial. United States v Duffy, 3 USCMA 20, 11 CMR 20; see also United States v Schick, 6 USCMA 493, 20 CMR 209. True, the issue of sanity is given a “preferred rating” in military law, in that the question can be raised at later stages of the case, but the preference is for the benefit of the accused, not the Government. United States v Burns, 2 USCMA 400, 9 CMR 30; United States v Schick, supra. Thus, paragraph 124 of the Manual for Courts-Martial, United States, 1951, provides that if it appears “from the record of trial or otherwise” that further inquiry into the accused’s mental condition is appropriate, a reviewing authority may direct that such inquiry be made “regardless of whether any such question [insanity] was raised at the trial or how it was determined if raised.” If insanity is raised and litigated at the trial, the Government cannot support the findings of guilty with evidence available before trial which it did not present, or with evidence obtained after the trial.
Here, the prosecution’s case in chief consisted of morning report entries showing the initiation and voluntary termination of the period of unauthorized absence. In defense, the accused maintained that at the time of the-commission of the offense his mental state was such that, while he could distinguish right from wrong, he could not adhere to the right. To support the defense, he introduced expert and lay testimony bearing upon his mental condition.
The defense showed that the accused had first served as a noncommissioned officer. During a tour of duty in 1954 in French Morocco, he was with the Fourth Radio Relay Squadron. He was considered to be a “very conscientious NCO”; quiet and “serious about the moral aspects of life.” It also appears that in 1958 he was selected for, and graduated from, Officer Candidate School and commissioned a Second Lieutenant. About July 1958, he was assigned to the 3380th Technical School, Keesler Air Force Base, for a fifty-one week course in electronics. *446At school the accused was regarded by his classmates as the best student in the class. On the basis of in-class and out-of-class associations, Major R. P. Eberle, the class leader, was of the opinion that the accused’s “character is . . . the highest . . . [he had] ever observed’-’; he said if he had a thousand officers from which to choose those to serve under him, the accused would be his “number one choice.” 'The accused moved ahead of his regular class, and completed the course in •about “half the time.” While with his regular class, on his own volition, the accused helped other members who had difficulty in understanding the assigned material. The accused “impressed” Captain H. C. Aim, Jr., one of the members of the original class, as being of “very high moral standing.”
On November 28, 1958, the accused went absent without leave. He remained away until December 10. Captain Olive, who knew the accused as an enlisted man in Africa, “was shocked” when he learned of the accused’s absence. He believed the accused “must have been under extreme stress.” Captain Aim was also ■“shocked” when he learned of the incident, “as [was] the rest of the class.” Major Eberle was “completely shaken up” because the act was “foreign” to his “thinking of the way he [the accused] was.” Neither Captain Aim nor Major Eberle had noticed any “perceptible change” in the accused’s attitude in their associations with him and he did not appear to them to be under stress. However, two civilian psychiatrists, testifying for the accused, said that at the time of his unauthorized absence the accused suffered from an acute dissociative reaction which so affected his capacity for rational judgment that he could not adhere to the right.
Dr. Charles D. Myers testified by deposition. He said he graduated from Louisiana State University Medical School in June 1945. Since March 1951, he was engaged exclusively in the practice of psychiatry and was certified as a specialist in that field by the American Board of Psychiatry and Neurology. He examined the accused on March 17, 1959, for about one hour. On the basis of his examination, he was of the opinion that, at the time of the offense, the accused suffered from an acute dissociative reaction. During the course thereof the accused had no capacity for rational judgment and was subject to an “overwhelming desire” to escape from the situation in which he found himself. As a result, while the accused knew it was “wrong to go AWOL,” he was “powerless to control his flight.” In Dr. Myers opinion, if the accused had been restrained from leaving it was “likely” he would have developed a fugue state or amnesia or a “catatonic reaction.” 1 According to Dr. Myers, the situation from which the accused was compelled to escape was this:
“9th Interrogatory: in your opinion how did this behavior of his . . . come about?
“Answer: In order to answer this I think is it important that I review some of the history as given by this man which, briefly, is I believe somewhat as follows: We have here a young man of apparently a rather rigid, driving ambitious personality structure, who had been under a great deal of strain for a long period of time, both in his training program *447and in Ms family life. I refer to his wife’s illness and her departure from Biloxi. Following this he engaged in some behavior which was definitely contrary and completely at variance to his own moral code. I think as a result of the guilt which he felt and the realization that he had violated his own rather strict moral codes, he became panic stricken on the morning in question. His capacity for rational judgement [sic] left him, and for a period of some six to eight days he was in this state which is described as an acute dissociative reaction.”
Dr. G. T. Sheffield also testified for the defense. He was a medical doctor with experience in neuropsychiatry since 1922. In 1946 he was certified by the American Board of Psychiatry. Among positions he held in the course of his medical career was that of Chief, Neuropsychiatric Service, Veterans’ Hospital, Biloxi, Mississippi. Additionally, Dr. Sheffield very frequently testified in criminal cases and in veterans’ competency proceedings. He examined the accused on two separate occasions. On the basis of his examination, and data provided by the base psychiatrist, which was of “immeasurable help,” he concluded the accused suffered from a dissociative reaction during which he “was trying to run from himself.” The reaction is an “impelling force” and the accused “could not control his actions.” The accused’s intelligence was not an offsetting circumstances, and if the accused had been stopped from going absent without leave, he “might have had a complete break with reality.” Dr. Sheffield explained his diagnosis as follows:
“You take an individual that was reared in rather strict religious surroundings and has high ideals, is very conscientious or, you might say, the overconscientious type of individual, and then for him to work very hard trying to accomplish his course — -as I understand it, he was trying to put a 52 week course into 24 weeks — well, now, he probably was plenty tired from a mental standpoint, and we don’t always realize how tired our minds become. All right — that, plus the fact that he evidently did some dreaming when he was playing the piano, because he was trying to get release from tension. This happened several days before he went AWOL — if I may be permitted to say that. And then because of the distance he was going, to play the piano, he elected to play in a bar which was nearby then he drank some liquor, which he never had been accustomed to doing and which was unusual; then his relationships — -supposed relationships — with a girl, which was absolutely foreign to his nature, and all contrary to his conscience. Now, speaking of conscience, or like some of us might say, his judge or super-ego — you know I’m trying to couch this thing in language we’ll all understand — you see that was so traumatic to him until he just couldn’t take it, and of course it’s really amazing to me he didn’t develop a frank psychotic episode, but apparently it was just a dissociative thing, which was a partial separation of his mind, or splitting of it; so he just couldn’t take it, and it was flight.”
Testifying on the characteristics of the dissociative reaction, Dr. Sheffield said that a break in the pattern of conduct is “usually” sudden, but the “precipitating factors may be gradual.” He also said he did not think that lay persons associated with the accused during the course of the reaction would recognize the accused’s mental condition.
To rebut the defense medical testimony, the Government introduced no medical evidence of its own; instead, it called Eleanor Marie Davis. She was the woman whose relationship with the accused, according to the defense psychiatrists, precipitated the accused’s dissociative reaction. She testified she was married, but indicated she was not living with her husband and she used the “Miss” form of address. She was employed as a barmaid. She first met the accused on November 15 or 18, 1958. That evening he drove her to Louisiana. On the *448following Saturday, he picked her up in Louisiana and returned her to Biloxi, Mississippi. Every night thereafter they “saw each other.” The accused told her he had been married, but that his wife had died; his two children were with his mother. The accused did not know that Miss Davis was married. A day or so before the offense, the accused “said something” about “going AWOL,” but she “didn’t think no more of it” until “right before” the accused met her on November 28 and told her he was absent without authority. “[A] 11 of a sudden” they “just left.”
The accused said that he was going to go to Michigan, but Miss Davis preferred California. To satisfy her, they agreed on California. According to Miss Davis, it did not seem to make any difference to the accused where he went. They were “going to go out there and get married.” Apparently, on November 28 the accused took his Oldsmobile car to a place “back of Popps Ferry” and parked it there; he then purchased a 1950 Plymouth. The accused told the witness he “didn’t want them to catch him before be got out of the State.” The accused also bought a “set of rings” and gave it to Miss Davis when they left. En route to California, Miss Davis disclosed that she was married. She and the accused talked about a divorce for her, but “there wasn’t no further plans made of it” and “no more was said about it.” Arriving in California, they went to Long Beach and Los Angeles. The accused looked for and found employment. At first he used another name but then he’ “gave them the correct one.” The accused worked for one day. When he returned that evening, Miss Davis suggested they return to Mississippi “and he said, all right, and so . . . [they] packed up and came back.” The return trip took about three or four days with the accused doing most of the driving. There was very little conversation by the accused and Miss Davis. As she said, “he didn’t hardly talk.” Asked if there was anything “wrong” the accused replied, “ ‘The less I talk the better things will be.’ ”
About two weeks after their return to Biloxi, Miss Davis telephoned the accused at the base, and learned that he was in the psychiatric ward of the base hospital. She succeeded in reach-, ing him by telephone at the hospital.! He told her “they thought something! was wrong with him.” He told her' about his wife and attributed his ¡ earlier representation that she was1 dead to the fact he was “mixed up.”! The final part of Miss Davis’ testimony, important to the issue before! us, is the following question and answer.
“Q. Marie, the time that you knew him before you left on this trip for California, and while on this trip, in your observation of him were his actions any different on the two different occasions comparing them with each other?
“A. No, not as I can say. They were all the same. He was the same when I first met him and went on the trip as any other time.”
Guilt must be established by the Government beyond a reasonable doubt. The Government’s burden extends not only to the elements of the offense charged, but also to the sanity of the accused. In the absence of evidence raising a question of the accused’s mental capacity, the Government can rely upon the common experience of mankind that most men are sane. United States v Biesak, 3 USCMA 714, 14 CMR, 132. But if evidence is introduced which raises the issue of insanity, the accused’s mental responsibility must be proved beyond a reasonable doubt. United States v Burns, supra. If the evidence of sanity offered by the Government is! not sufficiently probative to show beyond a reasonable doubt that the accused was sane at the time of the commission of the offense, an appellate, court is bound to set aside the findings of guilty. Fielding v United States, 251 F2d 878 (CA DC Cir) (1957); Wright v United States, 250 F2d 4 (CA DC Cir) (1957). Appellate defense counsel maintain that on the basis of the evidence presented at the trial, reasonable minds *449cannot escape a reasonable doubt as to the accused’s sanity. In substance, they contend the conduct of the accused during his association with Miss Davis was so incongruous with his normal behavior that it fits precisely into the complusive behavior pattern described by the defense psychiatrists and that the two factors, conduct and psychiatric evaluation, “inevitably raise a doubt of sanity.”
Peculiarities of conduct are not necessarily indicative of a state of mind which absolves a person from responsibility for his criminal acts. Also, it must be remembered that a person may be mentally ill from a medical standpoint, but still have sufficient mental capacity to be legally responsible for acts in violation of the penal law. The mere fact a person engages in conduct which is foreign to the image of him held by his family and friends does not necessarily point to a mental defect of a kind which makes him legally unaccountable for the act. The embezzler, for example, is ofttimes a paragon of virtue in his community. Here, however, there is evidence of more than a difference in conduct. Two experts on the operations of the mind, whose qualifications were conceded by the Government, testified that the accused’s conduct was the result of a mental disease and that he could not adhere to the right. Their testimony was uncontradicted. If credited, the testimony goes further than raising a reasonable doubt of the accused’s sanity; it would, in fact, establish that he was not legally accountable for his act. United States v Smith, 5 USCMA 314, 17 CMR 314; United States v Kunak, 5 USCMA 346, 17 CMR 346.
Psychiatry is not an exact science and psychiatrists differ in their opinions on the existence or the extent of certain aberrations in a particular individual. United States v Schick, supra; United States v Dunnahoe, 6 USCMA 745, 21 CMR 67; Holloway v United States, 148 F2d 665 (CA DC Cir) (1945). However, the testimony of a medical expert which is not impeached or discredited cannot be arbitrarily ■disregarded. Wirz v Wirz, 96 Cal App 2d 171, 214 P2d 839, 843. In fact, the Manual for Courts-Martial, United States, 1951, indicates that the testimony of the medical expert “may be given greater weight than that of a lay witness.” Paragraph 122c, Manual for Courts-Martial, United States, 1951, page 203. In the Dunnahoe case we pointed out that, especially for the purpose of drawing the line between psychoneurotic disorder and a personality disorder, “courts must rely on the expert witness.” The question, then, is whether the record contains evidence sufficient to support the court-martial’s finding of sanity, despite the testimony of Drs. Myers and Sheffield.
The fact that the medical testimony for the defense is not contradicted by other medical testimony on behalf of the prosecution does not necessarily mean reasonable men must entertain a reasonable doubt as to the accused’s sanity. A finding of guilty, which includes a finding of sanity contrary to expert opinion, can be sustained if it is supported by substantial evidence. Holloway v United States, supra; United States v Gundelfinger, 102 F Supp 177 (WD Pa) (1952); see also United States v Burns, supra. The opinion of a psychiatrist on the medical aspects of the accused’s mental condition does not define the scope of the responsibility of the court-martial. The court must consider all the evidence, assigning to each item the weight to which it is entitled. In some instances, the opinion of the medical expert that the accused is mentally incompetent may not be outweighed by the other evidence of sanity. Thus, in Fielding v United States, supra, the Court of Appeals for the District of Columbia set aside the accused’s conviction on the ground that the Government had failed to prove the accused’s sanity beyond a reasonable doubt. There, as here, the only medical testimony as to the accused’s mental condition was introduced by the defense. However, the two psychiatrists that *450testified for the accused did so on the “basis of their examination of appellant under hospital conditions over a long period,” while the lay testimony presented by the Government came from police officers, who merely arrested and questioned the accused on the day of the offense, and from persons related to the accused who “were out of touch with appellant . . . until just before” the offense. In other cases, the opinion of the expert may be so materially weakened by his own omissions or by other circumstances as to justify the triers of facts in giving little weight to the opinion. United States v Gundelfinger, supra.
Dr. Myers testified that part of the accused’s history, upon which he based his opinion that the accused was unable to adhere to the right, included the fact that the accused “had been under a great deal of strain for a long period of time, both in his training program [extending from Officer Candidate School to the electronics course] and in his family life.” Dr. Sheffield, however, maintained he did not think “there was anything wrong with . , . [the accused’s] home life”; he said the accused was “probably” overworked and worried about the illness of the accused wife and daughter, and these circumstances had “some bearing” on the situation. He indicated the two things “threw” the accused were, first, the fact that he “never drank” before the incident, and, second, the nature of his relationship with Miss Davis, “which he had never done before.” Thus, Dr. Myers’ opinion was materially affected by the lesser importance Dr. Sheffield attached to the accused’s work and family relations. Dr. Myers and Dr. Sheffield disagreed as to the time of the onset of the dissociative reaction. Dr. Sheffield believed it occurred when the accused played the piano at a bar, which was at the beginning of the period of the accused’s association with Miss Davis; whereas, Dr. Myers testified the accused became “panic stricken on the morning in question [November 28].” Also, it appears Dr. Sheffield’s opinion was subject to a substantial limitation. As extensive as was his background in psychiatry, he did not recall whether he had ever previously seen this “exact type of case.” He had to do some reading on the subject, “because you don’t see these cases every day.”
Besides the differences between, and limitations of, the medical opinions, the doctors’ testimony is contradicted by substantial lay testimony by persons who were in a position to observe the accused over a considerable period of time. Major Eberle and Captain Aim attended class with the accused for ten - weeks. According to their testimony, the accused handled the course material without any difficulty and he showed no sign of being under stress as a result of his school work. Further, there is no evidence the accused was not “accustomed” to liquor before the offense, which was the one of the two circumstances strongly relied upon by Dr. Sheffield in his conclusion that the accused could not adhere to the right. Miss Davis was with the accused before the dissociative reaction. She was with him a great deal of time during the dissociation reaction and immediately after he, in Dr. Sheffield’s words, “came to out in California”; during all that time the accused’s actions “were all the same.” True, on the return ride from California she was moved to ask the accused what was “wrong,” but she did so only because he was not very talkative. His disinclination to talk is fully explained by his answer, namely, that the “less” he said “the better things will be.”
Considering all the evidence, in our opinion, the court-martial could find, notwithstanding the medical testimony, that the accused could, beyond a reasonable doubt, adhere to the right. As the Court of Appeals for the District of Columbia said in the Holloway case, supra, page 667.
“A complete reconciliation between the medical tests of insanity and the moral tests of criminal responsibility is impossible. The purposes are different; the assumptions behind the two standards are differ*451ent. For that reason the principal function of a psychiatrist who testifies on the mental state of an abnormal offender is to inform the jury of the character of his mental disease. The psychiatrist’s moral judgment reached on the basis of his observations is relevant. But it cannot bind the jury except within broad limits. To command respect criminal law must not offend against the common belief that men who talk rationally are in most cases morally responsible for what they do.”
The decision of the board of review is affirmed.
Judge Latimer concurs in the result.In the course of Dr. Myers’ testimony, he was asked about two opinions given by Colonel L. E. Gatto, Senior Consultant in Psychiatry, Keesler Air Base Hospital. In his first opinion, which was given in his examination during the Article 32 investigation, Colonel Gatto said the accused could not adhere to the right by reason of conflicts and motivations within him at the time of the offense. In his second opinion, which was contained in a certificate filed in conjunction with two other military doctors, Colonel Gatto said the accused’s “ability to adhere to the right is considered to have - been partially impaired.” (Emphasis supplied.) These opinions were not admitted in evidence on the merits, and the law officer specifically instructed the court members they were not to be considered “for the purpose of establishing the truth of the matters asserted therein,” but only as part of the questioning of Dr. Myers.