A criminal conspiracy is generally a partnership formed to commit a crime or crimes. A criminal conspiracy exists when two or more persons form an agreement to violate a law that includes criminal penalties, and then take one or more steps designed to accomplish the goal of the conspiracy.

Federal and state statutes make criminal conspiracies illegal for two primary purposes: (1) to help combat the powerful forces created when two or more people collaborate to commit a crime; and (2) to allow criminal prosecutors (state and federal) to prosecute persons who play a role in planning a crime but who are not involved in the physical acts taken to complete the underlying crime.

For example, under federal law, if two or more persons conspire either to commit any offense against the United States, or to defraud the United States, or any agency of the United States in any manner or for any purpose, and one or more of such persons do any act to accomplish the objective of the conspiracy, each of the conspirators may be fined under and imprisoned for up to five years. See 18 U.S.C. §371. And most states have statutes (usually located in the penal or criminal code) that make criminal conspiracies a crime and include significant punishment upon conviction.

In Connecticut, criminal conspiracy is defined under state law as an agreement between two or more persons to commit a crime, followed by an overt act in furtherance of the conspiracy. The state statutes specifically address the issue of conspiracy in various sections of the penal code, recognizing the seriousness of collaborative efforts to commit crimes. The statutes are designed to deter and punish not only the commission of the criminal acts themselves but also the planning and agreement that precede them. This allows for the prosecution of individuals who have contributed to the criminal scheme, even if they did not participate in the actual commission of the crime. Penalties for conspiracy in Connecticut vary depending on the nature of the crime that was the object of the conspiracy, with the potential for fines and imprisonment. The federal law, as outlined in 18 U.S.C. §371, similarly criminalizes conspiracies to commit any offense against the United States or to defraud the United States, with penalties including fines and imprisonment for up to five years. Both state and federal laws reflect a commitment to thwarting criminal partnerships before they can bring their plans to fruition.