A judicial

Judiciary

The judiciary is the system of courts that interprets and applies the law in the name of the state. The judiciary also provides a mechanism for the resolution of disputes...

 executioner is a person who carries out a death sentence

Capital punishment

Capital punishment, the death penalty, or execution is the sentence of death upon a person by the state as a punishment for an offence. Crimes that can result in a death penalty are known as capital crimes or capital offences. The term capital originates from the Latin capitalis, literally...

 ordered by the state

State (polity)

A state is an organized political community, living under a government. States may be sovereign and may enjoy a monopoly on the legal initiation of force and are not dependent on, or subject to any other power or state. Many states are federated states which participate in a federal union...

 or other legal

Law

Law is a system of rules and guidelines which are enforced through social institutions to govern behavior, wherever possible. It shapes politics, economics and society in numerous ways and serves as a social mediator of relations between people. Contract law regulates everything from buying a bus...

 authority, which was known in feudal terminology as high justice

High Justice

High Justice is a 1974 collection of science fiction short stories by Jerry Pournelle. It was republished in a omnibus edition with Exiles to Glory in 2009 as Exile -- and Glory....

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The executioner was usually presented with a warrant authorizing or ordering him to execute the sentence. The warrant protects the executioner from the charge of murder

Murder

Murder is the unlawful killing, with malice aforethought, of another human being, and generally this state of mind distinguishes murder from other forms of unlawful homicide...

. Common terms for executioners derived from forms of capital punishment—though they often also performed other physical punishments—include hangman (hanging) and headsman (beheading).