Executioner
A judicial executioner is a person who carries out a death sentence ordered by the state or other legal authority, which was known in feudal terminology as high justice.
Scope and job
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. Common terms for executioners derived from forms of capital punishment—though they often also performed other physical punishments—include hangman (hanging) and headsman (beheading). In the military, the role of executioner was performed by a soldier, such as the provost. A common stereotype of an executioner is a hooded medieval or absolutist executioner.
While this task can be an occasional one, it can be carried out in the line of more general duty by an officer of the court, the police, prison staff, or even the military. A special case is the tradition of the Roman fustuarium, continued in forms of running the gauntlet, where the culprit receives his punishment from the hands of the comrades gravely harmed by his crime, e.g. for failing in vital sentinel duty or stealing from a ship's limited food supply.