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Comm. law, war. A passport or permission from a neutral state to persons who are thus authorized to go and return in safety, and, sometimes, to carry away certain things, in safety. According to common usage, the term passport is employed on ordinary occasions, for the permission given to persons when there is no reason why they should not go where they please: and safe-conduct is the name given to the instrument which authorizes certain persons, as enemies, to go into places where they could not go without danger, unless thus authorized by the government.

A safe-conduct is also the name of an instrument given to the captain or master of a ship to proceed on a particular voyage: it usually contains his name and residence, the name, description and destination of the ship, with such other matters as the practice of the place requires. This document is indispensably necessary for the safety of every neutral ship.

The act of congress of April 30th, 1790, s. 27, punishes the violation of any safe-conduct or passport granted under the authority of the United States, on conviction, with imprisonment, not exceeding three years, and a fine at the discretion of the court. Vide Conduct; Passport; and 18 Vin. Ab. 272.