The judge can't see the wood for the trees!
He heard a noise,he had the presence of mind to get his gun but not at any-point ascertain where Reva was?
Turn the light on perhaps,call her name and wait for answer-no!
Just go and unload your gun through the bathroom door having not located your girlfriend-sheer madness.
It has to be murder as he purposely fired the shots,knowing it would most certainly take someones life.