Definition and Elements.

A conspiracy is a combination of two or more persons, by some concerted action to accomplish some criminal or unlawful purpose, or to accomplish some purpose not in itself criminal or unlawful, by criminal or unlawful means.1

A formal agreement is not essential to constitute this offense. Persons may join a conspiracy already formed and in progress, and in doing so they become responsible for all acts done by any of the others before or after its formation.2

By the common law, at least three persons must join in the offense to make it a conspiracy.3

In some states the bare agreement to break the law without the doing of any overt act is sufficient;4 and this is true although it may be impossible to accomplish the object of the conspiracy.