21 U.S.C. § 875

(a) Power of Attorney General In carrying out his functions under this subchapter, the Attorney General may hold hearings, sign and issue subpenas, administer oaths, examine witnesses, and receive evidence at any place in the United States. (b) Procedures applicable Except as otherwise provided in this subchapter, notice shall be given and hearings shall be conducted under appropriate procedures of subchapter II of chapter 5 of title 5.