C.R.S. § 18-2-204

(1) 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. (2) 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. (3) If an individual abandons the agreement, the conspiracy is terminated as to him only if and when he gives timely notice to those with whom he conspired of his abandonment and the notice is evidenced by circumstances corroborating the giving of the same, or he informs the law enforcement authorities, having jurisdiction, of the existence of the conspiracy and of his participation therein.