Funny I interrupt it to mean he was working on a gun, they startled him (not seeing them come in), he turned in his seat still holding the gun and was shot by an office 4 times.
And..."seated by a workbench to the left of the pedestrian door." Means he was twisting to the left , with the gun in the right hand, there would be no intent to point the gun, it just traveled with him in his twisting motion.
He may have misjudged the danger to that motion, but no need to put 4 slugs put into him for it.
A good lawyer will have a field day with this report.