Conspiracy is a separate offense, by which someone conspires or agrees with someone else to do something which, if actually carried out, would amount to another federal crime or offense. It is an agreement or a kind of partnership for criminal purposes in which each member becomes the agent or partner of every other member. It is not necessary to prove that the criminal plan actually was accomplished or that the conspirator was involved in all stages of the planning or knew all of the details involved. The main elements that need to be proven are a voluntary agreement to participate and some overt act by one of the conspirators in furtherance of the criminal plan. If a person has an understanding of the unlawful nature of a plan and knowingly and willfully joins in that plan on one occasion, that is sufficient to convict him for conspiracy even though he had not participated before and even though he played only a minor part. A conspiracy may exist when the parties use legal means to accomplish an illegal result, or to use illegal means to achieve something that in itself is lawful.
Wheel and chain conspiracies are two types of conspiracies described in prosecuting offenders. A chain conspiracy involves parties linked together in a linear fashion. Typical drug or firearm smuggling organizations are chain conspiracies. It may consist of a series of drug deals, from manufacturer to the street dealer. In a wheel conspiracy, the ringleader is the "hub" and subsidiary parties are the "spokes". It is generally easier for prosecution to prove that a "chain" constituted a single conspiracy than it is to prove that a "wheel" was a single organization