delivered the opinion of the Court.
The question in this case is whether a Selective Service local board must reopen the classification of a registrant who claims that his conscientious objection to war in any form crystallized between the mailing of his notice to report for induction and his scheduled induction date. The petitioner before us made no claim to conscientious objector status until after he received his induction notice. Before the induction date, he then wrote to his local board and asked to be allowed to present his claim. He represented that his views had matured only after the induction notice had made immediate the prospect of military service. After Selective Service proceedings not material here, the petitioner’s local board notified him that it had declined to reopen his classification because the crystallization of his conscientious objection did not constitute the “change in the registrant’s status resulting from circumstances over which the registrant had no control” required for post-induction notice reopening under a Selective Service regulation.1 The petitioner then refused to submit'to induction, and a grand jury in the United States District Court for the Northern District of California indicted him for violation of the Military Selective Service Act of 1967.2
*101The petitioner waived trial by jury, and the District Court, holding that ripening of conscientious objector views could not be a circumstance over which a registrant had no control, found the petitioner guilty. The conviction was affirmed by the United States Court of Appeals for the Ninth Circuit, sitting en banc, and we granted certiorari, 397 U. S. 1074, to resolve a conflict among the circuits over the interpretation of the governing Selective Service regulation.3
A regulation explicitly providing that no conscientious objector claim could be considered by a local board unless filed before the mailing of an induction notice would, we think, be perfectly valid, provided that no inductee could be ordered to combatant training or service before a prompt, fair, and proper in-service determination of his claim. The Military Selective Service Act of 1967 confers on the President authority “to prescribe the necessary rules and regulations to carry out the provisions of this title . . . 50 U. S. C. App. §460 (b)(1). To read out of the authority delegated by this section the power to make reasonable timeliness rules would render it impossible to require the submission, before mailing *102of an induction notice, of a claim matured before that time. The System needs and has the power to make reasonable timeliness rules for the presentation of claims to exemption from service.4
A regulation barring post-induction notice presentation of conscientious objector claims, with the proviso mentioned, would be entirely reasonable as a timeliness rule. Selective Service boards must already handle prenotice claims, and the military has procedures for processing conscientious objector claims that mature in the service. Allocation of the burden of handling claims that first arise in the brief period between notice and induction seems well within the discretion of those concerned with choosing the most feasible means for operating the Selective Service and military systems. Further, requiring in-service presentation of post-notice claims would deprive no registrant of any legal right and would not leave a “no man's land” time period in which a claim then arising could not be presented in any forum.
The only unconditional right conferred by statute upon conscientious objectors is exemption from combatant training and service.5 The Selective Service law, indeed, provides for noncombatant training and service for those objectors to whose induction there is no obs*103tacle.6 The right to civilian service “in lieu of . . . induction” arises only if a registrant’s “claim is sustained by the local board.” It does not follow, given the power to make reasonable timeliness rules, that a registrant has an unconditional right to present his claim to the local board before induction, any more than he has such a right after induction. Congress seems rather carefully to have confined the unconditional right created by the statute to immunity from combatant training and service. Consequently, requiring those whose conscientious objection has not crystallized until after their induction notices to present their claims after induction would work no deprivation of statutory rights, so long as the claimants were not subjected to combatant training or service until their claims had been acted upon.
That those whose views are late in crystallizing can be required to wait, however, does not mean they can be deprived of a full and fair opportunity to present the merits of their conscientious objector claims for consideration under the same substantive criteria that must guide the Selective Service System. See Welsh v. United States, 398 U. S. 333. The very assertion of crystallization just before induction might cast doubt upon the *104genuineness of some claims, but there is no reason to suppose that such claims could not be every bit as bona fide and substantial as the claims of those whose conscientious objection ripens before notice or after induction. It would be wholly arbitrary to deny the late crystallizer a full opportunity to obtain a determination on the merits of his claim to exemption from combatant training and service just because his conscientious scruples took shape during a brief period in legal limbo.7 A system in which such persons could present their claims after induction, with the assurance of no combatant training or service before opportunity for a ruling on the merits, would be wholly consistent with the conscientious objector statute.8
The regulation we must interpret in this case does not unambiguously create such a system. Rather, it bars post-notice reopening “unless the local board first specifically finds there has been a change in the registrant's status resulting from circumstances over which the registrant had no control.” It is clear that the regulation was meant to cover at least such nonvolitional changes as injury to the registrant or death in his family making him the sole surviving son. The Government urges that *105the regulation be confined to just such "objectively identifiable” and “extraneous” events and circumstances. The petitioner contends that post-notice crystallization of conscientious objection is both a “circumstance” within the meaning of the regulation and one over which the registrant has no control.
We need not take sides in the somewhat theological debates about the nature of “control” over one’s own conscience that the phrasing of this regulation has forced upon so many federal courts. Rather, since the meaning of the language is not free from doubt, we are obligated to regard as controlling a reasonable, consistently applied administrative interpretation if the Government’s be such. Immigration Service v. Stanisic, 395 U. S. 62, 72; Thorpe v. Housing Authority, 393 U. S. 268, 276; Udall v. Tallman, 380 U. S. 1, 16-17; Bowles v. Seminole Rock & Sand Co., 325 U. S. 410, 413-414.
The Government argues for an interpretation identical in effect with the unambiguous rule hypothecated above, which, we have said, would clearly be a reasonable timeliness rule, consistent with the conscientious objector statute. The Government’s interpretation is a plausible construction of the language of the actual regulation, though admittedly not the only possible one. Given the ambiguity of the language, it is wholly rational to confine it to those “objectively identifiable” and “extraneous” circumstances that are most likely to prove manageable without putting undue burdens on the administration of the Selective Service System. It appears, moreover, that this position has been consistently urged by the Government in litigation when it was not foreclosed by adverse local precedent.
There remains for consideration whether the conditions for the validity of such a rule, discussed above, are met in practice. It appears undisputed that when an inductee *106presents a prima facie claim of conscientious objection that complies with timeliness rules for in-service cog-nizability, he is given duty involving the minimum practicable conflict with his asserted beliefs.9 It is thus evident that armed forces policy substantially meets the requirement of no combat training or service before an opportunity for a ruling on the claim.
As for the absence of any no man's land, the pertinent military regulations are somewhat inconsistent in their phrasing, perhaps because of the sharp division among the courts of appeals. They contain language appearing to recognize the obligation of the service to hear the claims of those whose alleged conscientious objection has crystallized between notice and induction, but they also contain formulations seeming to look the other way.10 *107We are assured, however, by a letter included in the briefs in this case from the General Counsel of the Department of the Army to the Department of Justice, that present practice allows presentation of such claims, and that there thus exists no possibility that late crystallizers will find themselves without a forum in which to press their claims.11 Our conclusion in this case is based upon that assurance.12 For if, contrary to that assurance, a situation should arise in which neither the local board nor the military had made available a full opportunity to present a prima facie conscientious objection claim for determination under established criteria, see Welsh v. United States, supra, a wholly different case would be presented.
Given the prevailing interpretation of the Army regulation, we hold that the Court of Appeals did not misconstrue the Selective Service regulation in holding that *108it barred presentation to the local board of a claim that allegedly arose between mailing of a notice of induction and the scheduled induction date. Accordingly the judgment of the Court of Appeals for the Ninth Circuit is
Affirmed.
32 CFR § 1625.2 (1971) provides, in pertinent part:
“[T]he classification of a registrant shall not be reopened after the local board has mailed to such registrant an Order to Report for Induction ... or an Order to Report for Civilian Work and Statement of Employer . . . unless the local board first specifically finds there has been a change in the registrant’s status resulting from circumstances over which the registrant had no control.”
Military Selective Service Act of 1967, § 12 (a), 50 U. S. C. App. §462 (a) (1964 ed., Supp. V), provides in pertinent part:
“[A]ny person . . . who . . . refuses . . . service in the armed forces ... or who in any manner shall knowingly fail or neglect or refuse to perform any duty required of him under or in the *101execution of this title . . . shall, upon conviction in any district court of the United States of competent jurisdiction, be punished by imprisonment for not more than five years or a fine of not more than $10,000, or by both such fine and imprisonment . . .
In accord with the position of the Ninth Circuit, see United States v. Al-Majied Muhammad, 364 F. 2d 223, 224 (CA4); Davis v. United States, 374 F. 2d 1, 4 (CA5); United States v. Taylor, 351 F. 2d 228, 230 (CA6) (semble).
Contra, United States v. Gearey, 368 F. 2d 144, 150 (CA2), 379 F. 2d 915 (after remand), cert. denied, 389 U. S. 959; Scott v. Commanding Officer, 431 F. 2d 1132, 1136 (CA3); United States v. Nordlof, 440 F. 2d 840 (CA7); Keene v. United States, 266 F. 2d 378, 384 (CA10); Swift v. Director of Selective Service, — U. S. App. D. C. —, 448 F. 2d 1147. See also United States v. Stoppelman, 406 F. 2d 127, 131 n. 7 (CA1) (dictum), cert. denied, 395 U. S. 981.
The power of the Selective Service System to set reasonable time limits for presentation of claims, with the penalty of forfeiture for noncompliance, seems never to have been questioned by any court. See, e. g., United States v. Gearey, 368 F. 2d 144, 149 and n. 9 (CA2).
The statute on conscientious objection begins:
“Nothing contained in this title . . . shall be construed to require any person to be subject to combatant training and service in the armed forces of the United States who, by reason of religious training and belief, is conscientiously opposed to participation in war in any form.” Military Selective Service Act of 1967, §6 (j), 81 Stat. 104, 60 U. S. C. App. §456 (j) (1964 ed., Supp. V).
Ibid.:
“Any person claiming exemption from combatant training and service because of such conscientious objections whose claim is sustained by the local board shall, if he is inducted into the armed forces under this title ... be assigned to noncombatant service as defined by the President, or shall, if he is found to be conscientiously opposed to participation in such noncombatant service, in lieu of such induction, be ordered by his local board, subject to such regulations as the President may prescribe, to perform for a period equal to the period prescribed in [Military Selective Service Act of 1967, §4(b), 50 U. S. C. App. §454 (b)] such civilian work contributing to the maintenance of the national health, safety, or interest as the local board pursuant to Presidential regulations may deem appropriate . . . .”
Since such a “no man’s land” would be intolerable, our decision today simply involves settling in which forum late crystallizers must have an opportunity for a ruling on the merits. Whether they must have such an opportunity at all cannot be open to question. Of course, a claimant who, after induction, declined to utilize available administrative procedures or who failed to observe reasonable and properly publicized time cutoffs might forfeit his claim.
There is no reason to suppose that a Selective Service local board, faced with the need to fill its monthly quotas, would be more sensitive in applying the legal standards that govern all conscientious objector claims than would the Army, whose mission is to train inductees as members of military units of maximum effectiveness and morale.
Department of Defense Directive No. 1300.6, § VI B (May 10, 1968):
“With respect to persons who have already served a portion of their obligated service who request discharge or non-combatant service for conscientious objection, the following actions will be taken:
“2. Pending decision on the case and to the extent practicable the person will be employed in duties which involve the minimum conflict with his asserted beliefs. . . .”
Army Regulation No. 635-20, ¶ 6a (July 31, 1970):
“[I]ndividuals who have submitted formal applications ... for discharge based on conscientious objection will be retained in their units and assigned duties providing the minimum practicable conflict with their asserted beliefs pending a final decision on their applications. In the case of trainees, this means that they will not be required to train in the study, use, or handling of arms or weapons. . . .”
See Army Regulation No. 635-20, ¶3:
“a. Consideration will be given to requests for separation based on bona fide conscientious objection to participation in war, in any form, when such objection develops subsequent to entry into the military service.
“b. Federal courts have held that a claim to exemption from *107military service under Selective Service laws must be interposed prior to notice of induction, and failure to make timely claim for exemption constitutes waiver of the right to claim. . . . Requests for discharge after entering military service will not be favorably considered when—
“(1) Based on conscientious objection which existed, but which was not claimed prior to notice of induction, enlistment or appointment.”
See also Department of Defense Directive No. 1300.6, § IV B 2.
“You also asked whether the Army allows a soldier to file for discharge in instances where his conscientious objector views are fixed after notice of induction but prior to entry into the military service. Present practice grants the soldier the opportunity to file in such cases.”
The letter additionally explains the composition and operation of the Army 1-0 Conscientious Objector Review Board, which has the responsibility of ruling on applications for conscientious objector discharges. The Board is composed of a senior officer, an officer in the Judge Advocate General Corps, a chaplain, and a Medical Corps officer. Only two votes are required to approve an application.
The same letter from the General Counsel of the Department of the Army reports that the identical interpretation prevailed in 1965, when the petitioner first was ordered to report for induction.