When can you arrest someone without a warrant?

The ability to arrest someone without a warrant is fundamentally rooted in the concept of probable cause. This refers to the reasonable belief that a law enforcement officer has that a person has committed a crime or is about to commit a crime. Probable cause is a constitutional standard necessary to justify various actions by law enforcement, including arrests.

When an officer has probable cause, they can act immediately to detain or arrest an individual without the need for a warrant. This principle is essential for allowing officers to perform their duties effectively while also respecting individuals' rights.

While witnessing a crime firsthand might provide probable cause, it is not the only situation in which an officer can make a warrantless arrest. Personal suspicion alone is insufficient, as mere suspicion does not meet the legal threshold of probable cause. Additionally, while incidents that occur during a traffic stop might provide cause for arrest, they are specific situations that still require the underlying factor of probable cause to be applicable.

In essence, warrantless arrests hinge primarily on the existence of probable cause, making this the correct choice.