The Office of International Affairs will assist the prosecutor in choosing the proper means for obtaining evidence from abroad. In general, the methods are grouped in three broad categories: formal requests (see this Manual at 275-277), informal means (278), and subpoenas (279). Formal requests include: (A) letters rogatory, (B) treaty requests, and (C) requests under executive agreements. Informal requests use ad hoc methods to secure assistance, often more quickly and flexibly than by formal means, but the evidence obtained may not always conform to the Federal Rules of Evidence or otherwise be admissible in a United States proceeding. Subpoenas are a unilateral way to obtain evidence.
Updated June 8, 2015