A peace officer, without a warrant, may arrest a person if the officer has probable cause to believe: 1. A felony has been committed.The authority to arrest depends on the existence of a crime or arrest warrant; without a crime or arrest warrant, there can be no arrest. A warrantless arrest is usually a "strike while the iron is hot" situation. During an arrest, police officers detain a person in police custody, often because they are suspected of committing a crime. There are two main types of warrants: (1) warrants for the arrest of a person and (2) warrants to search for personal property, persons, or items. If you willingly give consent for the search, then officers do not need a warrant or probable cause to search. If you get arrested in Maricopa County, the police must read you your Miranda rights, otherwise known as the Miranda warning. The goal of law enforcement is to charge you with and eventually have you convicted of a crime. Arrest warrants: These are issued when there is probable cause to believe that a person has committed a crime.