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In many states the traditional distinctions between the culpability of accomplices and principals to a crime have been replaced by statute—including the felony murder rule that may make an accomplice guilty of first degree or capital murder if he was the lookout or getaway driver for a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 Minnesota, the concept of a criminal accomplice is covered under the state's aiding and abetting statutes. According to Minnesota law, a person is criminally liable for a crime as an accomplice if they intentionally aid, advise, hire, counsel, or conspire with or otherwise procure the other to commit the crime. This means that an accomplice does not have to physically commit the crime themselves to be held responsible; being a lookout or getaway driver, as in the example provided, would make someone an accomplice. Minnesota law does not distinguish between principals and accomplices in terms of liability; both can be charged and convicted of the same crime. Furthermore, under the felony murder rule in Minnesota, if a death occurs during the commission of a felony or in the immediate flight from it, all participants can be charged with first-degree murder, regardless of their role in the underlying felony. This means that an accomplice to a bank robbery that results in death could potentially face first-degree murder charges, even if they were not the individual who directly caused the death.