A criminal accomplice is a person who knowingly, voluntarily, or intentionally assists another person in the commission of a crime—or under some circumstances, a person who fails to prevent another person from committing a crime. Unlike a person who aids and abets a crime by helping with the planning of the crime but is often not present at the scene of the crime—and unlike an accessory after the fact, who is not present at the scene of the crime but assists after the commission of the crime to help the perpetrator avoid arrest or punishment—an accomplice actively participates in the commission of the crime. For example, a person who acts as a lookout or getaway driver for a bank robbery is an accomplice.

In many states the traditional distinctions between the culpability of accomplices and principals to a crime have been replaced by statute—including the felony murder rule that may make an accomplice guilty of first degree or capital murder if he was the lookout or getaway driver for a bank robbery that resulted in a death.

In Alabama, an individual who assists in the commission of a crime is considered an accomplice and is subject to criminal liability. Under Alabama law, a person is legally accountable for the behavior of another constituting a criminal offense if, with the intent to promote or assist the commission of the offense, they aid or abet the principal offender. This includes situations where the accomplice is present at the crime scene in a supportive role, such as acting as a lookout or a getaway driver during a bank robbery. Alabama's complicity statutes do not require the accomplice to have been physically present at the scene of the crime to be held liable. Furthermore, under the felony murder rule in Alabama, an accomplice can be charged with first-degree murder if a death occurs during the commission of a felony, even if the accomplice's role was limited to assistance rather than directly causing the death. This reflects the state's approach to holding all participants in a felony accountable when a life is lost, regardless of their specific role in the underlying crime.