He was apparently seen by a helicopter breaking into cars and a house nearby.
He had his cell phone in his hand, Police saw something, they thought it was a gun and told him to drop the gun and raise his hands. If he followed orders, dropped the phone and raised his hands, he would not have gotten shot.
"...seen by a helicopter..."
You should not be so quick to believe everything cops say. Like most other people, they will lie if it helps them cover their asses.
But he made it to grammas house. Safety zone! /s