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In many states the traditional distinctions between the culpability of accomplices and principals to a crime have been replaced by statute—including the felony murder rule that may make an accomplice guilty of first degree or capital murder if he was the lookout or getaway driver for a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 West Virginia, the concept of a criminal accomplice is addressed under state statutes that define criminal complicity. An accomplice in West Virginia is someone who knowingly, voluntarily, or intentionally provides assistance in the commission of a crime. This can include actions such as acting as a lookout or a getaway driver during the commission of a crime like a bank robbery. West Virginia law does not strictly adhere to the traditional distinctions between principals and accomplices; instead, it recognizes that anyone who participates in the commission of a felony or misdemeanor in any way can be charged as if they had committed the act themselves. Furthermore, under the felony murder rule in West Virginia, an accomplice can be charged with first-degree murder if a death occurs during the commission of certain felonies, such as a bank robbery, even if the accomplice's role was limited to being a lookout or getaway driver. This reflects the state's approach to holding all participants in a crime responsible for the outcomes of the criminal activity.