Authors:

You obviously don't have to be a murderer to play a murderer or you don't have to be a dictator to play a dictator. So, you're an actor. You come up with whatever you come up with to play that part.

"Robert Duvall’s talks about his faith-themed film “Seven Days in Utopia” — and why he’s not into “message movies”". Interview with John W. Kennedy, www.beliefnet.com. 2011.
You obviously don't have to be a murderer to play a murderer or you don't have to be a dictator to play a dictator. So, you're an actor. You come up with whatever you come up with to play that part.