Section 3328 of title 5 of the United States Code provides that —

(a) An individual —   (1) Who was born after December 31, 1959, and is or was required to register under section 3 of the Military Selective Service Act (50 U.S.C. App. 453); and   (2) Who is not so registered or knowingly and willfully did not so register before the requirement terminated or became inapplicable to the individual, shall be ineligible for appointment to a position in an executive agency of the Federal Government.

(b) The Office of Personnel Management, in consultation with the Director of the Selective Service System, shall prescribe regulations to carry out this section. Such regulations shall include provisions prescribing procedures for the adjudication within the Office of determinations of whether a failure to register was knowing and willful. Such procedures shall require that such a determination may not be made if the individual concerned shows by a preponderance of the evidence that the failure to register was neither knowing nor willful.