Which of the following best defines a citizen's arrest?

• A. A police officer's official arrest under color of law.
• B. A non-official arrest by a private person for a crime they witnessed; subject to limitations and potential liability.
• C. A court-ordered detention.
• D. A routine traffic stop.

Answer: (B)

A citizen’s arrest is a private person detaining someone they believe has committed a crime, as an informal restraint rather than an official police action. The key idea here is that the action is taken by a member of the public, not by law enforcement, and it must be limited by legal rules. The person making the arrest should have factual grounds—typically they witnessed the crime or have probable cause—and they must use only reasonable force. They’re expected to turn the suspect over to police promptly and can face liability if the detention is unlawful or excessive.

This fits best because it describes a private, non-official arrest tied to a witnessed crime and acknowledges the limitations and potential liability involved. It’s not describing an official police arrest under color of law, nor a court-ordered detention, nor a routine traffic stop.