In what scenario may police make a warrantless arrest?

A warrantless arrest by law enforcement is legally permissible when a law enforcement officer witnesses a felony being committed. This is grounded in the principle of allowing police to act swiftly to address crime and protect public safety. When an officer sees a felony in progress, they have immediate and direct evidence of the crime occurring, which justifies making an arrest without a warrant.

In contrast, while police may suspect individuals of criminal behavior or may have reasonable grounds to believe they have committed a crime, these alone do not meet the legal threshold for a warrantless arrest. For minor offenses or misdemeanors, officers often require additional justification or may not be able to arrest without a warrant, depending on jurisdictional laws. Likewise, merely appearing suspicious does not provide sufficient legal grounds for an arrest; there must be observable evidence of criminal activity. Thus, the scenario wherein an officer directly observes a felony being committed provides the strongest basis for a lawful, warrantless arrest.