A criminal charge of aiding and abetting is known as an accomplice crime, and may be brought against anyone who helps with the commission of a crime. Aiding and abetting charges vary from state to state (and under federal law), but generally require that the defendant knowingly and intentionally aided and abetted the principal(s) in each essential element of the underlying crime. A person charged with aiding and abetting is often not present when the underlying crime is committed, but has knowledge of the crime before the crime is committed, and assists with the commission of the crime by providing information, action, or financial support. If the person aiding and abetting has a sufficient degree of involvement in the crime, the participation may rise to the level of being a conspiracy to commit the underlying crime.

In Oregon, aiding and abetting is addressed under the state's criminal laws concerning liability for conduct of another person. According to ORS 161.155, a person is criminally liable for the conduct of another if, with the intent to promote or facilitate the commission of the crime, they aid or abet or agree or attempt to aid the other person in planning or committing the crime. The law does not require the accomplice to be physically present at the scene of the crime; knowledge of the crime and intentional assistance in its commission are sufficient for liability. The aider and abettor can be charged and convicted even if the principal offender is not prosecuted or convicted. The penalties for aiding and abetting depend on the underlying crime committed and can be as severe as those for the principal offender. This reflects the state's view that accomplices play a critical role in the commission of crimes and should be held accountable to a similar extent as those who directly engage in criminal acts.