A warrant is usually a court order authorizing law enforcement officers to make an arrest or conduct a search. Warrants normally issued by a court include search warrants, arrest warrants, and bench warrants. A typical arrest warrant in the United States will take the approximate form of: "This Court orders the Sheriff or Constable to find the named person, wherever he may be found, and deliver said person to the custody of the Court."
Generally, only the Judge or Court Commissioner can vacate, or cancel, a warrant. In most instances an in-person appearance by the defendant is required to cancel a warrant.