delivered the opinion of the Court.
This is a habeas corpus proceeding instituted in the District Court by the petitioner, presently confined in Saint Elizabeths Hospital for the insane pursuant to a commitment under D. C. Code § 24-301 (d), to test the legality of his detention. The District Court, holding that petitioner had been unlawfully committed, directed his release from custody unless civil commitment proceedings (D. C. Code § 21-310) were begun within 10 days of the court’s order. The Court of Appeals, sitting en banc, reversed by a divided vote. 109 U. S. App. D. C. 404, 288 F. 2d 388. Since the petition for certiorari raised important questions regarding the procedure for confining the criminally insane in the District of Columbia and suggested possible constitutional infirmities in § 24-301 (d) as applied in the circumstances of this case, we granted the writ. 366 U. S. 958.
Two informations filed in the Municipal Court for the District of Columbia on November 6. 1959, charged petitioner with having violated D. C. Code § 22-1410 by drawing and negotiating checks in the amount of $50 each with knowledge that he did not have sufficient funds or credit with the drawee bank for payment. On the same day, petitioner appeared in Municipal Court to answer these charges and a plea of not guilty was recorded. He was thereupon committed under D. C. Code § 24-301 (a) to the District of Columbia General Hospital for a mental examination to determine his competence to stand trial.1 On December 4,/1959, the Assistant Chief Psychiatrist of *707the Hospital reported that petitioner’s mental condition was such that he was then “of unsound mind, unable to adequately understand the charges and incapable of assisting counsel in his own defense.” The case was continued while petitioner was given treatment at the General Hospital.
On December 28, 1959, the Assistant Chief Psychiatrist sent a letter to the court advising that petitioner had “shown some improvement and at this time appears able to understand the charges against him, and to assist counsel in his own defense.” This communication also noted that it was the psychiatrist’s opinion that petitioner “was suffering from a mental disease, i. e., a manic depressive psychosis, at the time of the crime charged,” such that the crime “would be a product of this mental disease.” As for petitioner’s current condition, the psychiatrist added that petitioner “appears to be in an early stage of recovery from manic depressive psychosis,” but that it was “possible that he may have further lapses of judgment in the near future.” He stated that it “would be advisable for him to have a period of further treatment in a psychiatric hospital.”
Petitioner was brought to trial the following day in the Municipal Court before a judge without a jury. The record before us contains no transcript of the proceedings,2 but it is undisputed that petitioner, represented by counsel, sought at that time to withdraw the earlier plea of not guilty and to plead guilty tp both informations. The trial judge refused to allow the change of plea, apparently on the basis of the Hospital’s report that petitioner’s commission of the alleged offenses was- the product of mental illness.
*708At the trial one pf the prosecution’s witnesses, a physician representing the General Hospital’s Psychiatric Division, testified, over petitioner’s objection, that petitioner’s crimes had been committed as a result of mental illness. Although petitioner never claimed that he had not been mentally responsible when the offenses were committed and presented no evidence to support an acquittal by reason of insanity, the trial judge concluded that petitioner was “not guilty on the ground that he was insane at the time of the commission of the offense.” 3 The court then ordered that petitioner be committed to Saint Elizabeths Hospital as prescribed by D. C. Code § 24-301 (d), which reads:
“(d) If any person tried upon an indictment or information for an offense, or tried in the juvenile court of the District of Columbia for an offense, is acquitted solely on the ground that he was insane at the time of its commission, the court shall order such person to be confined in a hospital for the mentally ill.”
There can be no doubt as to the effect of this provision with respect to a defendant who has asserted a defense of insanity at some point during the trial. By its plain terms it directs confinement in a mental hospital of any criminal defendant in the District of Columbia who is “acquitted solely on the ground” that his offense was committed while he was mentally irresponsible, and forecloses the trial judge from exercising any discretion in this regard. Nor does the statute require a finding by the trial judge or jury, or by a medical board, with respect to the accused’s mental health on the date of the judgment of acquittal. The sole necessary and sufficient condition for bringing the compulsory commitment provision into *709play is that the defendant be found not guilty of the crime with which he is charged because of insanity “at the time of its commission.” 4 Petitioner does not contend that the statute was misinterpreted in these respects.
Petitioner maintains, however, that his confinement is illegal for a variety of other reasons, among which is the assertion that the “mandatory commitment” provision, as applied to an accused who protests that he is presently sane and that the crime he committed was not the product of mental illness, deprives one so situated of liberty without due process of law.5 We find it unnecessary to con*710sider this and other constitutional claims concerning the fairness of the Municipal Court proceeding, since we read § 24-301 (d) as applicable only to a defendant acquitted on the ground of insanity who has affirmatively relied upon a defense of insanity, and not to one, like the petitioner, who has maintained that he was mentally responsible when the alleged offense was committed.6
The decisions of this Court have repeatedly warned against the dangers of an approach to statutory construction which confines itself to the bare words of a statute, e. g., Church of the Holy Trinity v. United States, 143 U. S. 457, 459-462; Markham v. Cabell, 326 U. S. 404, 409, for “literalness may strangle meaning,” Utah Junk Co. v. Porter, 328 U. S. 39, 44. Heeding that principle we conclude that to construe § 24-301 (d) as applying only to criminal defendants who have interposed a defense of insanity is more consistent with the general pattern of laws governing the confinement of the mentally ill in the District of Columbia, and with the congressional policy that impelled the enactment of this mandatory commitment provision, than would be a literal reading of the section. That construction finds further support in the rule *711that a statute should be interpreted, if fairly possible, in such a way as to free it from not insubstantial constitutional doubts. E. g., United States v. Jin Fuey Moy, 241 U. S. 394, 401; International Assn. of Machinists v. Street, 367 U. S. 740, 749. Such doubts might arise in this case were the Government’s construction of § 24-301 (d) to be accepted.
I.
To construe § 24-301 (d) as requiring a court, without further proceedings, automatically to commit a defendant who, as in the present case, has competently and advisedly not tendered a defense of insanity to the crime charged and has not been found incompetent at the time of commitment is out of harmony with the awareness that Congress has otherwise shown for safeguarding those suspected of mental incapacity against improvident confinement.
Thus, a civil commitment must commence with the filing of a verified petition and supporting affidavits. D. C. Code § 21-310. This is followed by a preliminary examination by the staff of Saint Elizabeths Hospital, a hearing before the Commission on Mental Health, and then another hearing in the District Court, which must be before a jury if the person being committed demands one. D. C. Code § 21-311. At both of these hearings representation by counsel or by a guardian ad litem is necessary. Dooling v. Overholser, 100 U. S. App. D. C. 247, 243 F. 2d 825, construing D. C. Code §§ 21-308, 21-311. The burden of proof is on the party seeking commitment, and it is only if the trier of fact is “satisfied that the alleged insane person is insane,” that he may be committed “for the best interest of the public and of the insane person.” D. C. Code § 21-315.7
*712Likewise, Congress has afforded protection from improvident commitment to an accused in a criminal case who appears to the trial court “from the court’s own observations, or from prima facie evidence submitted to the court ... [to be] of unsound mind or . . . mentally incompetent so as to be unable to understand the proceedings against him or properly to assist in his own defense.” D. C. Code § 24-301 (a). In such circumstances preliminary commitment for a “reasonable period” is authorized in order to permit observation and examination. If the medical report shows that the accused is of unsound mind, the court may “commit by order the accused to a hospital for the mentally ill unless the accused or the Government objects.” (Emphasis, added.) In case of objection, there must be a judicial determination with respect to the accused’s mental health, and it is only “if the court shall find the accused to be then of unsound mind or mentally incompetent to stand trial” that an order for continued commitment is permissible. Hence if the accused denies that he is mentally ill, he is entitled to a judicial determination of his present mental state despite the hospital board’s certification that he is of .unsound mind. And it should be noted that the burden rests with the party seeking commitment to prove that the accused is “then of unsound mind.” D. C. Code § 24^-301 (a).
Considering the present case against this background, we should be slow in our reading of § 24^301 (d) to attribute to Congress a purpose to compel commitment of *713an accused who never throughout the criminal proceedings suggests that he is, or ever was, mentally irresponsible.8 This is the more so when there is kept in mind the contrast between the nature of an acquittal by reason of insanity and the finding of insanity required in other kinds of commitment proceedings. In the District of Columbia, as in all federal courts, an accused “is entitled to an acquittal of the specific crime charged if upon all the evidence there is reasonable doubt whether he was capable in law of committing crime.” Davis v. United States, 160 U. S. 469, 484. See, e. g., Isaac v. United States, 109 U. S. App. D. C. 34, 284 F. 2d 168. Compare Leland v. Oregon, 343 U. S. 790. Consequently, the trial judge or jury must reach a judgment or verdict of not guilty by reason of insanity even if the evidence as to mental responsibility at the time the offense was committed raises no more than a reasonable doubt of sanity. If § 24-301 (d) were taken to apply to petitioner’s situation, there would be an anomalous disparity between what *714§ 24-301 (d) commands and what § 24 — 301 (a) forbids. On the one hand, § 24-301 (d) would compel posttrial commitment upon the suggestion of the Government and over the objection of the accused merely on evidence introduced by the Government that raises a reasonable doubt of the accused’s sanity as of the time at which the offense was committed. On the other hand, § 24-301 (a) would prohibit pretrial commitment upon the suggestion of the Government and over the objection of the accused, although the record contained an affirmative medical finding of present insanity, unless the Government is able to prove, by a preponderance of the evidence, that the accused is presently of unsound mind.
Of course the posttrial commitment of § 24^301 (d) presupposes a determination that the accused has committed the criminal act with which he is charged, whereas pretrial commitment antedates any such finding of guilt. But the fact that the accused has pleaded guilty -or that, overcoming some defense other than insanity, the Government has established that he committed a criminal act constitutes only strong evidence that his continued liberty could imperil “the preservation of public peace.” It no more rationally justifies his indeterminate commitment to a mental institution on a bare reasonable doubt as to past sanity than would any other cogent proof of possible jeopardy to “the rights of persons and of property” in any civil commitment. Compare note 7, supra.
Moreover, the literal construction urged here by the Government is quite out of keeping with the congressional policy that underlies the elaborate procedural precautions included in the civil commitment provisions. It seems to have been Congress’ intenti<?n to insure that only those who need treatment and may be dangerous are confined; committing a criminal defendant who denies the existence of any mental abnormality merely on the *715basis of a reasonable doubt as to his condition at some earlier time is surely at odds with this policy.
The criminal defendant who chooses to claim that he was mentally irresponsible when his offense was committed is in quite a different position. It is true that he may avoid the ordinary criminal penalty merely by submitting enough evidence of an abnormal mental condition to raise a reasonable doubt of his responsibility at the time of committing the offense. Congress might have thought, however, that having successfully claimed insanity to avoid punishment, the accused should then bear the burden of proving that he is no longer subject to the same mental abnormality which produced his criminal acts. Alternatively, Congress might have considered it appropriate to provide compulsory commitment for those who successfully invoke an insanity defense in order to discourage false pleas of insanity. We need go no further here than to say that such differentiating considerations are pertinent to ascertaining the intended reach of this statutory provision.
II.
The enactment of § 24-301 (d) in 1955 was the direct result of the change in the standard of criminal responsibility in the District of Columbia wrought by Durham v. United States, 94 U. S. App. D. C. 228, 214 F. 2d 862. That decision provoked a congressional re-examination of the laws governing commitment of the criminally insane. "Apprehension that Durham would result in a flood of acquittals by reason of insanity and fear that these defendants would be immediately set loose led to agitation for remedial legislation.” Krash, The Durham Rule and Judicial Administration of the Insanity Defense in the District of Columbia, 70 Yale L. J. 905, 941 (1961). A Committee on Mental Disorder as a Criminal Defense was established *716by the Council on Law Enforcement in the District of Columbia to inquire into “the substantive and procedural law of the District of Columbia bearing on mental disorder as a defense in a criminal.prosecution.” S. Rep. No. 1170, 84th Cong., 1st Sess. 1 (1955); H. R. Rep. No. 892, 84th Cong., 1st Sess. 1 (1955). Among its recommendations was a mandatory commitment provision, subsequently enacted as §24^301 (d). The Committee noted that while under the then existing discretionary commitment statute 9 it had been customary for the court and the appropriate executive official to order the confinement of all those who had been found not guilty solely by reason of insanity, more assurance should be given the public that those so acquitted would not be allowed to be at large until their recovery from past mental illness had been definitely established:
“No recent cases have come to the attention of this Committee where a person acquitted in the District of Columbia of a crime on the sole ground of insanity has not been committed to a mental hospital for treatment. Nevertheless, the Committee is of the opinion that the public is entitled to know that, in every case where a person has committed a crime as a result of a mental disease or defect, such person shall be given a period of hospitalization and treatment to guard against imminent recurrence of some criminal act by that person.” (Emphasis in the original.)
*717“The Committee believes that a mandatory commitment statute would add much to the public’s peace of mind, and to the public safety, without impair-. ing the rights of the accused. Where accused has pleaded insanity as a defense to a crime, and the jury has found that the defendant was, in fact, insane at the time the crime was committed, it is just and reasonable in the Committee’s opinion that the insanity, once established, should be presumed to continue and that the accused should automatically be confined for treatment until it can be shown that he has recovered.” S. Rep. No. 1170, 84th Cong., 1st Sess. 13 (1955); H. R. Rep. No. 892, 84th Cong., 1st Sess. 13 (1955). (Emphasis added.)
It is significant to note that in finding that mandatory commitment would not result in “impairing the rights of the accused” and that it was “just and reasonable . .• . that the insanity, once established, should be presumed to continue . . . until it can be shown that . . . [the accused] has recovered,” the Committee Report, which was embraced in the reports of the Senate and House committees on the bill, spoke entirely in terms of one who “has pleaded insanity as a defense to a crime.” Certainly such confidence could hardly have been vouchsafed with respect to a defendant who, as in this case, had stoutly denied his mental incompetence at any time. And it is surely straining things to assume that any of the committees had in mind such cases as this, which are presumably rare.10
. Nor is it necessary to read § 24-301 (d) as an assurance that an accused who requires medical treatment will be *718hospitalized rather than be confined to jail. Simultaneously with the mandatory commitment provision, Congress enacted the present § 24-302, which permits transfers of mentally ill convicts from penal institutions to hospitals. Consequently, if an accused who pleads guilty is found to be in need of psychiatric assistance, he may be transferred to a hospital following sentence.
Finally, it is not necessary to accept the Government’s literal reading of § 24-301 (d) in order to effectuate Congress’ basic concern, in passing this legislation, of reassuring the public. Section 24-301 (a) provides a procedure for confining an accused who, though found competent to stand trial, is nonetheless committable as a person of unsound mind. That section permits the trial judge to act “prior to the imposition of sentence or prior to the expiration of any period of probation,” if he has reason to believe that the accused “is of unsound mind or is mentally incompetent so as to be unable to understand the proceedings against him.” (Emphasis added.) The statute provides for a preliminary examination by a hospital staff, and then “if the court shall find the accused to be then of unsound mind or mentally incompetent to stand trial, the. court shall order the accused confined to a hospital for the mentally ill.” 11 (Emphasis added.) *719This inquiry, therefore, is not limited to the accused’s competence to stand trial; the judge may consider, as well, whether the accused is presently committable as a person of unsound mind.12 Since this inquiry may be undertaken at any time “prior to the imposition of sentence,” it appears to be as available after the jury returns a verdict of not guilty by reason of insanity as before trial.
In light of the foregoing considerations we conclude that it was not Congress’ purpose to make commitment compulsory when, as here, an accused disclaims reliance on a defense of mental irresponsibility. This does not mean, of course, that a criminal defendant has an absolute right to have his guilty plea accepted by the court. As provided in Rule 11, Fed. Rules Crim. Proc., and Rule 9, D. C. Munic. Ct. Crim. Rules, the trial judge may refuse to accept such a plea and enter a plea of not guilty on behalf of the accused. We decide in this case only that if this is done and the defendant, despite his own assertions of sanity, is found not guilty by reason of insanity, *720§ 24-301 (d) does not apply. If commitment is then considered warranted, it must be accomplished either by resorting to § 24-301 (a) or by recourse to the civil commitment provisions in Title 21 of the D. C.' Code.
The judgment of the Court of Appeals is reversed and the case is remanded to the District Court for further proceedings consistent with this opinion.
It is so ordered.
Mr. Justice Frankfurter took no part in the decision of this case. Mr. Justice White took no part in the consideration or decision of this case.The record does not reveal the basis for the trial court’s action.
Despite the absence of a trial record, the District Court made findings of fact respecting the proceedings at petitioner’s trial, some of which are contested by the parties. We rely only upon those facts that were here admitted.
Petitioner did not appeal from this judgment.
Similar statutes are found in 12 States, the Virgin Islands, and in England. Compare Colo. Rev. Stat. Ann. (Supp. 1957) § 39-8-4; Ga. Code Ann., 1953, § 27-1503; Kan. Gen. Stat. Ann., 1949, § 62-1532; Maine Pub. L., 1961, c. 310; Mass. Ann. Laws, 1957, c. 123, § 101 (murder or manslaughter); Mich. Stat. Ann., 1954, § 28.933 (3) (murder); Minn. Stat. Ann. (Supp. 1957) § 631.19; Neb. Rev. Stat. Ann., 1943, § 29-2203; Nev. Rev. Stat., 1955, § 175.445; N. Y. Sess. Laws 1960, c. 550, §§ 1-3; Ohio Rev. Code (Baldwin 1953) § 2945.39; Wis. Stat., 1958, § 957.11; V. I. Code Ann., 1957, Tit. 5, § 3637. The English procedure is found in Trial of Lunatics Act, 46 & 47 Vict., c. 38, s. 2 (1883).
Statutes under which commitment is mandatory if the trial judge or jury finds that the accused is presently insane are, of course, clearly distinguishable. The focus of the inquiry on which commitment turns is the accused’s mental health as of the time of commitment, and the verdict of not guilty by reason of insanity is merely evidence bearing on that issue. Consequently, the effect of the compulsory aspect of such a commitment provision is by no means comparable to that involved in the present case. Similarly, any discretionary commitment statute presumably leaves the trial judge or jury free to find the accused presently sane and thus entitled to full liberty.
In essence the claim is that § 24^301 (d) compels the indeterminate commitment of such a person without any inquiry as to his present sanity, and solely on evidence sufficient to warrant a reasonable doubt as to his mental responsibility as of the time he committed the offense charged. The claim is said to be buttressed when § 24-301 (d) is taken in conjunction with the rigorous release-from-*710confinement provisions of § 24-301 (e) and § 24-301 (g) as construed by the Court of Appeals for the District of Columbia in Overholser v. Leach, 103 U. S. App. D. C. 289, 257 F. 2d 667; Ragsdale v. Overholser, 108 U. S. App. D. C. 308, 281 F. 2d 943.
The defense of insanity need not, of course, be asserted by means of a formal plea. Fed. Rules Crim. Proc. 11, which governs proceedings in the District Courts, permits the entry of certain enumerated pleas, not including “not guilty by reason of insanity,” a plea which is authorized in some jurisdictions. D. C. Munic. Ct. Crim. Rule 9 is identical to Fed. Rules Crim. Proc. 11. Consequently, a defense of insanity in a criminal proceeding in the District of Columbia may be established under a general plea of not guilty. We read § 24-301 (d) as making commitment mandatory whenever the defendant successfully relies, in any affirmative way, on a claim that he was insane at the time of commission of the crime of which he is accused.
A police officer may arrest and detain any person who appears to be of unsound mind on the belief that if such person is “permitted to remain at large or to go unrestrained in the District of Columbia *712the rights of persons and of property will be jeopardized or the preservation of public peace imperiled and the commission of crime rendered probable.” D. C. Code § 21-326. However, within 48 hours of such apprehension, the petition that is otherwise required for an involuntary commitment must be filed, and the procedural machinery which follows the filing of such a petition must be set in motion. D. C. Code § 21-311, par. 3.
In eight of the 13_ other American jurisdictions where statutes providing for mandatory commitment, following an acquittal by reason of insanity, are in effect, see note 4, supra, the provisions of the statutes indicate that they are to apply only if an insanity defense is interposed by the accused: Colorado (“in a trial involving the plea of not guilty by reason of insanity”); Georgia (“in all criminal trials . . . wherein an accused shall contend that he was insane”); Nebraska (accused “may plead that he is not guilty by reason of insanity or mental derangement”); Nevada (“where on a trial a defense of insanity is interposed by the defendant”); New York (“when the defense is insanity of the defendant”); Ohio (“when a defendant pleads ‘not guilty by reason of insanity’”); Wisconsin (“no plea that the defendant . . . was insane . . . shall be received unless it is interposed at the time of arraignment”); Virgin Islands (“if the defense is the mental illness of the defendant”). We have not been referred to any case in the remaining American jurisdictions or in England where a mandatory commitment of this nature, following a proceeding in which the defendant did not interpose a defense of insanity, was sustained.
The statute then in effect provided:
“If the jury shall find the accused to be then insane, or if an accused person shall be acquitted by the jury solely on the ground of insanity, the court may certify the fact to the Federal Security Administrator, who may order such person to be confined in the hospital for the .insane, and said person and his estate shall be charged with the expense of Ms support in the said hospital.” 59 Stat. 311. (Emphasis added.)
We have been told of four such cases in the District of Columbia, two arising in the Municipal Court and two in the District Court: District of Columbia v. Trembley, D. C. 28343-60; United States v. Taylor, U. S. 4774-59; United States v. Kloman, Crim. No. 383-58; United States v. Strickland, Crim. No. 374-59.
D. C. Code §24-301 (a) provides:
“(a) Whenever a person is arrested, indicted, charged by information, or is charged in the juvenile court of the District of Columbia, for or with an offense and, prior to the imposition of sentence or prior to the expiration of any period of probation, it shall appear to the court from the court’s own observations, or from prima facie evidence submitted to the court, that the accused is of unsound mind or is mentally incompetent so as to be unable to understand the proceedings against him or properly to assist in his own defense, the court may order the accused committed to the District of Columbia General Hospital or other mental hospital designated by the court, for such reasonable period as the court may determine for examination and observation and for care and treatment if such is *719necessary by the psychiatric staff of said hospital. If, after such examination and observation, the superintendent of the hospital, in the case of a mental hospital, or -the chief psychiatrist of the District of Columbia General Hospital, in the case of District of Columbia General Hospital, shall report that in his opinion the accused is of unsound mind or mentally incompetent, such report shall be sufficient to authorize the court to commit by order the accused to a hospital for the mentally ill unless the accused or the Government objects, in which event, the court, after hearing without a jury, shall malee a judicial determination of the competency of the accused to stand trial. If the court shall find the accused to be then of unsound mind or mentally incompetent to stand trial, the court shall order the accused confined to a hospital for the mentally ill.”
Compare 18 U. S. C. § 4244, considered in Greenwood v. United States, 350 U. S. 366, which relates only to “mental incompetency after arrest and before trial.” By the terms of 18 U. S. C. § 4246, commitment is to last only “until the accused shall be mentally competent to stand trial or until the pending charges against him are disposed of according to law.”