In United States criminal law, probable cause is the legal standard by which police authorities have reason to obtain a warrant for the arrest of a suspected criminal and for a court's issuing of a search warrant. One definition of the standard derives from the U.S. Supreme Court decision in the case of Beck v. Ohio (1964), that probable cause exists when “at [the moment of arrest] the facts and circumstances within [the] knowledge [of the police], and of which they had reasonably trustworthy information, [are] sufficient to warrant a prudent [person] in believing that [a suspect] had committed or was committing an offense.”