That's according to a new informal legal opinion from Wisconsin Attorney General J.B. Van Hollen.
Brown County attorney Frederick J. Mohr asked Van Hollen whether private guards at Austin Straubel International Airport could detain people if they didn't witness a crime.
Van Hollen said common law principles on citizen's arrests apply to guards.
They can legally detain someone if they have evidence the person committed a felony, even if the crime wasn't committed in the guard's presence. But they can't hold someone for a misdemeanor they didn't see happen.

