Definition - What does Warrantless Arrest mean?
A warrantless arrest is an arrest that occurs by a law enforcement officer who does not have a warrant to arrest that person.
In many instances, the police are required to have a warrant before they can arrest an individual. However, there are also a number of reasons why a police officer can arrest a person without a warrant.
Justipedia explains Warrantless Arrest
In order for law enforcement to properly make an arrest without a warrant, the officer must have sufficient probable cause to make the arrest. Almost all valid warrantless arrests are deemed to be valid due to some type of emergency situation occurring at the time of the arrest. For example, if an officer has probable cause to believe that a person is a danger to society, then the police officer can arrest that person without an arrest warrant.
Warrantless arrests can also occur if the police officer has reasonable belief that evidence will be destroyed, that a person is about to or has just committed a crime, that a suspect is a flight risk, or for several other reasons.
An example of a police officer making a legitimate warrantless arrest would be if they witness a man walking into a bank, wearing a mask, and holding a gun. In such a situation, the police officer would have reasonable belief that the man was about to rob the bank, and so a warrantless arrest would be justified.