A warrant is generally an order that serves as a specific type of authorization, that is, a writ issued by a competent officer, usually a judge or magistrate, that permits an otherwise illegal act that would violate individual rights in order to enforce the law and aid in investigations; affording the person executing the writ protection from damages if the act is performed.
In the United Kingdom, senior public appointments are made by warrant under the royal sign-manual, the personal signature of the monarch, on the recommendation of the government.
In an interesting survival from medieval times, these warrants abate (lose their force) on the death of the sovereign if they have not already been executed.
They were tied to stakes in Smithfield, an open market area in central London, and the firewood bundles were about to be lit, when a royal messenger rode up to announce that Mary I had died: the warrants for their death had lost their force.
[3] This law was one of the key acts of Great Britain which led to the American Revolution,[citation needed] and is the direct reason that the American Founding Fathers ensured that general warrants would be illegal in the United States by ratifying the Fourth Amendment to the U.S. Constitution in 1791.