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 New Hampshire, aiding and abetting is addressed under the accomplice liability statutes. According to NH Rev Stat § 626:8 (2021), a person is considered an accomplice to a crime if they purposely aid, agree to aid, or attempt to aid another person in planning or committing the crime. The statute also covers situations where an individual solicits another to commit a crime or gives advice or encouragement. It is not necessary for the accomplice to be present at the scene of the crime to be charged. The intent and knowledge of the accomplice regarding the crime are crucial factors in determining their liability. If the accomplice's actions or support were significant enough, they could also face charges of conspiracy in addition to aiding and abetting. The penalties for an accomplice are generally the same as for the principal offender, meaning that if convicted, the accomplice could face the same consequences as if they had committed the underlying crime themselves.