Concert-of-Action Rule Law and Legal Definition

Concert of action rule is a principle of criminal law that an agreement by two or more persons to commit a particular crime cannot be prosecuted as a conspiracy if the crime could not be committed except by the actual number of participants involved. But if an additional person participates so as to enlarge the scope of the agreement, all the actors may be charged with conspiracy. This doctrine is recognized by many courts, but in many cases it has been held to be inapplicable to the case presented. The rule is considered in modern legal thinking as an aid in construction of statutes, a presumption that the Legislature intended the general conspiracy section be merged with the more specific substantive offense.

This is also known as Wharton’s rule after the influential criminal-law author Francis Wharton.

The following are examples of caselaw on the rule:

Where the cooperation of two or more persons is necessary to the commission of the substantive crime, and there is no ingredient of an alleged conspiracy that is not present in the substantive crime, then the persons necessarily involved cannot be charged with conspiracy to commit the substantive offense and also with the substantive crime itself. This is the "concert of action rule" or Wharton's Rule.[People v. Mayers, 110 Cal. App. 3d 809, 815 (Cal. App. 4th Dist. 1980)]

Wharton's rule or the concert of action rule provides that : ". . . a combination to commit an offense which can only be committed by the concerted action of two persons does not amount to conspiracy if only those two are involved."[Perkins v. State, 26 Md. App. 526, 535 (Md. Ct. Spec. App. 1975)]