what is a posse

A posse is a group of people who come together for a common purpose or interest. The term originally referred to a group of people summoned by a sheriff to assist in preserving the public peace usually in an emergency. In a classic Western movie, when the sheriff gathers together a posse, its members usually work to find and arrest the bad guys. The term "posse comitatus" refers to a body or force armed with legal authority. Today, the word posse is used most often to refer to a group of friends or people with some common interest, in a somewhat joking way.