I've spoken to Sheriff Larry Dever - Cochise County Sheriff. I know him. I respect him. I trust his interpretation of the Arizona Statutes far more than I trust yours.
Now we're getting somewhere... How does he interpret the law?
Seems clear that Dumas and Co. were acting illegally. We won't even bring up the pistol-whipping.
13-3884. Arrest by private person A private person may make an arrest:
1. When the person to be arrested has in his presence committed a misdemeanor amounting to a breach of the peace, or a felony.
2. When a felony has been in fact committed and he has reasonable ground to believe that the person to be arrested has committed it.