18 U.S.C. § 3508 : US Code - Section 3508: Custody and return of foreign witnesses

Search 18 U.S.C. § 3508 : US Code - Section 3508: Custody and return of foreign witnesses

(a) When the testimony of a person who is serving a sentence, is
in pretrial detention, or is otherwise being held in custody, in a
foreign country, is needed in a State or Federal criminal
proceeding, the Attorney General shall, when he deems it
appropriate in the exercise of his discretion, have the authority
to request the temporary transfer of that person to the United
States for the purposes of giving such testimony, to transport such
person to the United States in custody, to maintain the custody of
such person while he is in the United States, and to return such
person to the foreign country.
(b) Where the transfer to the United States of a person in
custody for the purposes of giving testimony is provided for by
treaty or convention, by this section, or both, that person shall
be returned to the foreign country from which he is transferred. In
no event shall the return of such person require any request for
extradition or extradition proceedings, or proceedings under the
immigration laws.
(c) Where there is a treaty or convention between the United
States and the foreign country in which the witness is being held
in custody which provides for the transfer, custody and return of
such witnesses, the terms and conditions of that treaty shall
apply. Where there is no such treaty or convention, the Attorney
General may exercise the authority described in paragraph (a) if
both the foreign country and the witness give their consent.