Can you detain a person based on the word of a third party?

• A. Yes
• B. No
• C. Sometimes
• D. Only with police involvement

Answer: (B)

Detaining someone requires having evidence or seeing the behavior yourself—you need reasonable grounds based on your own observation or direct information tied to what you witnessed. Relying only on what a third party says isn’t enough to justify detention, because that information could be false, incomplete, or misleading. Taking someone into custody without solid, firsthand basis risks unlawful restraint and potential liability.

If you hear about a problem from a third party, your safer, proper steps are to observe discreetly if possible, note details (what you saw, what the other person said, descriptions), and involve authorities or your supervisor. You may only detain if you personally witness an offense or have immediate, valid evidence that a crime is in progress, and you have the lawful authority to do so. Otherwise, you should avoid detention and seek police involvement.

So this situation isn’t appropriate for detention based solely on a third-party report.