(1) (A) In any investigation of— (i) (I) a Federal health care offense; or (II) a Federal offense involving the sexual exploitation or abuse of children, the Attorney General; (ii) an unregistered sex offender conducted by the United States Marshals Service, the Director of the United States Marshals Service; or (iii) an offense under section 871 or 879, or a threat against a person protected by the United States Secret Service under paragraph (5) or (6) of section 3056, if the Director of the Secret Service determines that the threat constituting the offense or the threat against the person protected is imminent, the Secretary of the Treasury, may issue in writing and cause to be served a subpoena requiring the production and testimony described in subparagraph (B). (B) Except as provided in subparagraph (C), a subpoena issued under subparagraph (A) may require— (i) the production of any records or other things relevant to the investigation; and (ii) testimony by the custodian of the things required to be produced concerning the production and authenticity of those things. (C) A subpoena issued under subparagraph (A) with respect to a provider of electronic communication service or remote computing service, in an investigation of a Federal offense involving the sexual exploitation or abuse of children shall not extend beyond— (i) requiring that provider to disclose the information specified in section 2703(c)(2), which may be relevant to an authorized law enforcement inquiry; or (ii) requiring a custodian of the records of that provider to give testimony concerning the production and authentication of such records or information. (D) As used in this paragraph— (i) the term “Federal offense involving the sexual exploitation or abuse of children” means an offense under section 1201, 1591, 2241(c), 2242, 2243, 2251, 2251A, 2252, 2252A, 2260, 2421, 2422, or 2423, in which the victim is an individual who has not attained the age of 18 years; and (ii) the term “sex offender” means an individual required to register under the Sex Offender Registration and Notification Act ( 42 U.S.C. 16901 et seq.).