This publication has been superseded by Mutual Legal Assistance Treaties and Letters Rogatory: Obtaining Evidence and Assistance from Foreign Jurisdictions.

The investigation of transnational conduct often involves gathering evidence located in foreign countries. There are two primary means of obtaining evidence for use in a transnational proceeding: a Mutual Legal Assistance Treaty (MLAT) and a letter rogatory. This guide provides an overview of the statutory schemes and procedural matters that distinguish MLATs and letters rogatory, and it discusses legal issues that arise when the prosecution, the defense, or a civil litigant seeks to obtain evidence from abroad as part of a criminal or civil proceeding.