Trumper got a gun out first.

Other guy got a gun.

Trumper shot him once and jammed, other guy didn't jam.

And according to the survivor, the 80 year old trumper started the violence with a headbut.

Mr. Mathews had a .45-caliber handgun in his car. He fired first; when he pulled the trigger a second time, no bullet came out. Mr. Mattai had a 9-millimeter pistol in his car. He fired back at least four rounds. The bullets sprayed across Mr. Mathews’s car and into his open window as Mr. Mathews drove away. They pierced his door frame and the driver’s seat, missing him by inches.