“ 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. ”

“ 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. ”

“ 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 obstacle. ”