The Secretary of the Smithsonian Institution, subject to adequate security and other investigations as he may determine to be appropriate, and subject further to a prior determination by him that no qualified United States citizen is available for the particular position involved, is authorized to employ and compensate aliens in a scientific or technical capacity at authorized rates of compensation without regard to statutory provisions prohibiting payment of compensation to aliens.
20 USC § 46a
Employment of aliens by Secretary
through Pub. L. 116-344, except Pub. Ls. 116-260 and 116-283