Yes, they do:
The victor was presented with a golden medal (by the emperor).
The waiter was asked to close the window (by your wife).
It was clearly demonstrated by the prosecutor that etc.../ Their excellent motive was clearly demonstrated by the prosecutor.
His behaviour was resented by some.
I'm not sure the 3rd one will be much used. And in these cases (passive voices), the focus is on the subject (the victor, the waiter, the behaviour), not on the agent, so I think the speaker will often drop the agent.