What are Letters of Marque and Reprisal?

From Constitution.org

Letters of marque and reprisal are commissions or warrants issued to someone to commit what would otherwise be acts of piracy. They will normally contain the following first three elements, unless they imply or refer to a declaration of war to define the enemies, and may optionally contain the remainder:

1. Names person, authorizes him to pass beyond borders with forces under his command.
2. Specifies nationality of targets for action.
3. Authorizes seizure or destruction of assets or personnel of target nationality.
4. Describes offense for which commission is issued as reprisal.
5. Restriction on time, manner, place, or amount of reprisal.

Many of these documents were taken, with permission, from the Isle of Tortuga site, which is about piracy and letters of marque. Here is a link to our local copy of their Letters of Marque page.

The U.S. Constitution provides, Article I, Sec. 8 cl. 11:
The Congress shall have Power ... To declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;

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