An agreement between two or more persons to engage jointly in an unlawful or criminal act, or an act that is innocent in itself but becomes unlawful when done by the combination of actors.
Conspiracy is governed by statute in federal courts and most state courts. Before its Codification in state and federal statutes, the crime of conspiracy was simply an agreement to engage in an unlawful act with the intent to carry out the act.Federal statutes, and many state statutes, now require not only agreement and intent but also the commission of an Overt Act in furtherance of the agreement.
Conspiracy is a crime separate from the criminal act for which it is developed. For example, one who conspires with another to commit Burglary and in fact commits the burglary can be charged with both conspiracy to commit burglary and burglary.
Conspiracy is an inchoate, or preparatory, crime. It is similar to solicitation in that both crimes are committed by manifesting an intent to engage in a criminal act. It differs from solicitation in that conspiracy requires an agreement between two or more persons, whereas solicitation can be committed by one person alone.
Conspiracy also resembles attempt. However, attempt, like solicitation, can be committed by a single person. On another level, conspiracy requires less than attempt. A conspiracy may exist before a crime is actually attempted, whereas no attempt charge will succeed unless the requisite attempt is made.
The law seeks to punish conspiracy as a substantive crime separate from the intended crime because when two or more persons agree to commit a crime, the potential for criminal activity increases, and as a result, the danger to the public increases. Therefore, the very act of an agreement with criminal intent (along with an overt act, where required) is considered sufficiently dangerous to warrant charging conspiracy as an offence separate from the intended crime.
According to some criminal-law experts, the concept of conspiracy is too elastic, and the allegation of conspiracy is used by prosecutors as a superfluous criminal charge. Many criminal defence lawyers maintain that conspiracy is often expanded beyond reasonable interpretations. In any case, prosecutors and criminal defence attorneys alike agree that conspiracy cases are usually amorphous and complex.