Quote Munoz
"This can never, will never happen again on a United Airlines flight," he said.
He was asked what the company would do in future if a seated passenger refused voluntarily to leave an overbooked plane based on the airline's compensation offer.
"We're not going to put a law enforcement official to take them off," he said, "to remove a booked, paid seated passenger, we can't do that."
Mr Munoz was asked if Mr Dao was at fault.
The chief executive paused.
He said: "No. He can't be. He was a paying passenger sitting on our seat in our aircraft and no one should be treated that way. Period."