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In many states the traditional distinctions between the culpability of accomplices and principals to a crime have been replaced by statute—including the felony murder rule that may make an accomplice guilty of first degree or capital murder if he was the lookout or getaway driver for a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 Mississippi, the law does not distinguish significantly between the principal offender and the accomplice in terms of culpability. Both parties can be charged and punished equally under Mississippi Code Section 97-1-3. An accomplice is someone who aids, counsels, agrees to, or encourages the commission of a crime, and can be charged with the same offense as the principal. This includes situations where the accomplice acts as a lookout or getaway driver during the commission of a crime such as a bank robbery. Furthermore, under the felony murder rule, if a death occurs during the commission of a felony, such as a bank robbery, an accomplice can be charged with capital murder or first-degree murder, even if their role did not directly involve the act of killing. This reflects the state's approach to holding all participants in a crime responsible for the outcomes of the criminal activity, regardless of their specific role.