A leading actor or actress often has a supporting cast who assist in one way or another in the leading player's performance. Likewise, criminals are often assisted by others in the commission of crime.
Complicity is a broad doctrine that imposes criminal responsibility on individuals for a crime committed by someone else, usually because these secondary actors have intentionally helped or encouraged the primary actor to commit the crime. Complicity can also impose responsibility based on other criminal law doctrines such as conspiracy.
In this chapter we will focus on a form of complicity called accessorial or accomplice liability. In general, individuals who help another person to commit a crime are accessories or accomplices to that crime and are also responsible for its commission. Frequently, statutes and case law will use terms like “aid, abet, encourage, assist, advise, solicit, or procure” to describe the various kinds of conduct that can generate accomplice liability. (Note that complicity, including accomplice liability, is usually not a separate crime with its own punishment. It is simply one way of committing a crime.) Throughout this chapter we will call individuals who help another to commit a crime through such activities “accomplices.”
There are two ways of helping someone else commit a crime: