Committing a crime is a new mechanic from Outlaws of Thunder Junction.

Gerrard was the pinnacle of Urza's Legacy project and one of the main protagonists of the Weatherlight saga. Which doesn't stop him from committing a crime at least once per turn with his upkeep trigger, with a possibility to do some more crimes in the combat step.

Crovax was originally a Weatherlight crew member, but went on to become the Evincar of Rath and one of the main antagonists. He eats a creature every turn, but that is not a crime (sorry, Mirri!)

Karn Liberated, being a famous pacifist golem, commits crimes with two of his loyalty abilities. Elesh Norn Mother of the Machines, on the other hand, does nothing wrong!

Dovin, despite being an Architect of Law, doesn't mind committing crimes every turn as well. Unlike the Massacre Girl. She doesn't target, so her hands are clean.