Bill Maher supported his choice to have the performer Louis CK at a Mark Twain Prize event.
He said CK must not face a permanent blacklist for past mistakes.
Maher pointed to comparable figures of star who should be reconsidered.
At a chat with Donald Trump, Maher called Trump an unknown quantity.
He also appreciated Trump's focus on big-picture aims.
The Maher's remarks add to current conversations about comebacks in the comedy circuit.