Model Penal Code sec. 5.03

Section 5.03. Criminal Conspiracy.

(1) Definition of Conspiracy.  A person is guilty of conspiracy with another person or persons to commit a crime if with the purpose of promoting or facilitating its commission he:

(a) agrees with such other person or persons that they or one or more of them will engage in conduct which constitutes such crime or an attempt or solicitation to commit such crime;  or

(b) agrees to aid such other person or persons in the planning or commission of such crime or of an attempt or solicitation to commit such crime.

(2) Scope of Conspiratorial Relationship.  If a person guilty of conspiracy, as defined by Subsection (1) of this Section, knows that a person with whom he conspires to commit a crime has conspired with another person or persons to commit the same crime, he is guilty of conspiring with such other person or persons, whether or not he knows their identity, to commit such crime.

(3) Conspiracy With Multiple Criminal Objectives.  If a person conspires to commit a number of crimes, he is guilty of only one conspiracy so long as such multiple crimes are the object of the same agreement or continuous conspiratorial relationship.

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(5) Overt Act.  No person may be convicted of conspiracy to commit a crime, other than a felony of the first or second degree, unless an overt act in pursuance of such conspiracy is alleged and proved to have been done by him or by a person with whom he conspired.

(6) Renunciation of Criminal Purpose.  It is an affirmative defense that the actor, after conspiring to commit a crime, thwarted the success of the conspiracy, under circumstances manifesting a complete and voluntary renunciation of his criminal purpose.

(7) Duration of Conspiracy.  For purposes of Section 1.06(4):

(a) conspiracy is a continuing course of conduct which terminates when the crime or crimes which are its object are committed or the agreement that they be committed is abandoned by the defendant and by those with whom he conspired;  and

(b) such abandonment is presumed if neither the defendant nor anyone with whom he conspired does any overt act in pursuance of the conspiracy during the applicable period of limitation; and

(c) if an individual abandons the agreement, the conspiracy is terminated as to him only if and when he advises those with whom he conspired of his abandonment or he informs the law enforcement authorities of the existence of the conspiracy and of his participation therein.