Ariz. Rev. Stat. § 13-409 : — CRIMINAL CODEJUSTIFICATION —409 - Justification; use of physical force in law enforcement

A person is justified in threatening or using physical force against another if in making or assisting in making an arrest or detention or in preventing or assisting in preventing the escape after arrest or detention of that other person, such person uses or threatens to use physical force and all of the following exist:

1. A reasonable person would believe that such force is immediately necessary to effect the arrest or detention or prevent the escape.
2. Such person makes known the purpose of the arrest or detention or believes that it is otherwise known or cannot reasonably be made known to the person to be arrested or detained.
3. A reasonable person would believe the arrest or detention to be lawful.

A.R.S. § 13-409