Admiral Motti

Admiral Motti was the senior Imperial commander in charge of the daily
operations onboard the first Death star.
Admiral Motti disagreed with the way Vader handled things.
He was nearly killed once when he questioned Vaders reliance on the force. 
He called the force an archaic and outdated religion.
Vader in response started to choke the Admiral using the force 
until Grand Moff Tarkin oredered Vader to stop.
Admiral Motti died when the first Death Star was Destroyed.