Section
32, act Feb. 25, 1903, ch. 755, § 1,
32 Stat. 904, granted immunity from prosecution to witnesses testifying or producing evidence, documentary or otherwise, in any proceeding, suit, or prosecution under section
1 to
11 of this title. See section
6001 et seq. of Title 18, Crimes and Criminal Procedure.
Section
33, act June 30, 1906, ch. 3920,
34 Stat. 798, provided that, under the immunity provisions of former section
32 of this title, immunity was to extend only to a natural person who, in obedience to a subpoena, testified or produced evidence.