I may remember that one. That still doesn't make it right. A wounded person can easily kill you and drop dead. They can also stumble outside and kill someone else, including the first officers on the scene. Those few seconds are very important. If someone comes in using lethal force against me, they better not go crying to mama because I responded in kind.
The court made itself a laughing stock on the case you mentioned. A pharmacist is doing his job, and all of a sudden a man with a gun enters his pharmacy. The immediate fight or flight instincts take over. You get this adrenalin rush that you can barely control, and you respond by shooting the perp and finishing him off.
The court thinks you should be prepared for this, remain calm, and be as thoughtful about it as if you had weeks to prepare. Baloney. The benefit of the doubt goes to the guy who was minding and tending his own business. The perp sought him out, not the other way around.