Accomplice. Or it could be an Abettor.
accomplice
I was the accomplice to a crime
The plural of accomplice is accomplices
To the best of my knowledge there has never been a woman undertaker that was an accomplice to Jack The Ripper. It is more common for JTR type killers to work alone.
An accomplice is somebody who joins in with an activity of another person. Usually an accomplice is somebody that has helped a person commit a crime.
He is the accomplice of this crime.
The bank robber had an accomplice waiting outside in a car.
The Accomplice - 1915 is rated/received certificates of: USA:Approved
The question asnwered itself. you will be charged as an Accomplice to Murder.
The cast of The Weekender - 2008 includes: Thomas Aske Berg as Accomplice Dion DeRizzo as Jack Brent Fidler as Hostage
You couldn't have made this whole meal yourself, you must have had an accomplice.