This case in England would also be problematic here in America based upon excessive force laws. In no state are you allowed to kill an intruder simply because they are in the home or to protect property. You better damn well be able to prove that your life was in danger or you are going to jail. A big problem with most gun owners in this country is that they are totally ignorant of the laws pertaining to the use of deadly force. Plenty of Americans are also serving long prison sentences for killing an intruder but could not prove that their life was in danger. Too many people with a CCW think its a license to kill any criminal and their possession of a gun is actually a major liability. Protecting your property is not a justification of the use of deadly force in the eyes of the American courts either.
The article states the intruder "brandishes it as if to strike" this is the major weakness in the story. Cleverly worded however.
I would think it would be the prosecution's job to have to prove that the defendant's life wasn't in danger, no?