The shooters right hand is covered in blood because he was holding the AR with it and when he was killed instantly he slumped down on top of the gun with his hand underneath his head. That’s why it’s bloody. Look at the pic of him dead on the roof taken by one of the spectators. He’s resting on his side.
That’s awfully curious. His right hand is uniformly covered with blood, not as one might expect, to be covered only up to the lowest part that was adjacent to the roof as blood from his head would have flown past.
With such an exit wound behind his right ear “staring at all onlookers,” it couldn’t have seemed a possibility that he was anything but dead, such that a zip cuff would be totally unnecessary and would serve to pollute the crime scene far more than protect any LEO or bystander.
I know, someone will say it must have been department policy since back in ‘91 when some drug-crazed zombie came “back from the grave” to grab an officer’s gun and wound several bystanders.