Don’t need locks; a simple door stop wedge will keep the average person in quite well. Been there, done that.
See link at 103, doesn’t sound like they even tried to lock him in (be it real lock or wedge), he kept sticking his head out asking when it was his time to come do his reporter thing.
In order to avoid self-incrimination, or crippling embarrassment, I won't ask which side of the door you were on.