PHOENIX - Philip Brailsford, the former Mesa police officer on trial for murder, took the stand Wednesday in his own defense.

In 2016, Brailsford shot and killed Daniel Shaver while on duty in a Mesa hotel after responding to a call for a man pointing a gun out the window. Brailsford said he didn't know at the time but Shaver was unarmed.

"My hope was that no lethal force was going to be needed at all," Brailsford said.

During his testimony, Brailsford said that night, he was a cover officer.

"I'm responsible for everyone else including myself and I need to keep the scene safe," Brailsford said during his testimony.

Upon arrival, police ordered Shaver to get on the ground. Police body cameras were rolling. Brailsford said Shaver reached his right hand down to his waist in a motion that looked like a draw-stroke. Brailsford demonstrated the movement in court.

"Moving directly to the side, it looked exactly like someone was drawing a pistol," described Brailsford.

Brailsford fired his AR-15 rifle five times, shooting and killing Shaver. He said based on his training, he had reason to believe Shaver was armed.

"We are trained that we cannot wait until the gun comes into view," Brailsford explained.

Brailsford said he was concerned for the safety of everyone in the hotel hallway. He said he didn't find out Shaver was unarmed until the next day.

"I felt incredibly sad for him," Brailsford said. "I still couldn't understand why he would make that motion."

Prosecutors began to cross-examine Brailsford Wednesday before court concluded for the day. Brailsford's testimony is expected to continue Thursday morning.