I'm baaack!
Delos, you seem to give all the credit for reasonable thought to the other guy, and his "neighborhood watch". And we all know how succesful armed neighborhood watches have been. In the ops scenario, he did not cross the fence. While he may have crossed the property line, we do not know this.
I too carry extra magazines. I'm not sure what this has to do with it. I also adhere to the 21' rule. (and so does anyone aggressively approaching me)
As far as shooting a policeman in front of his own property, I'd shoot the Pope if he attacked me. I do not have to let anyone attack me.
While the OP mentioned the race of the individual, I was keeping my responses purely raceless.
Lets do some of it again. A recreational photographer would probably not know if he is in a high crime area. Actually I am the one trying to explain why someone might rush toward him a little bit faster than normal, if he is near an abandoned building. The sheriff or dispatcher always asks if the caller if he got a license number. When any farmer or anyone else has had burglary or vandalism and has frequently rushed out to get a license number, usually the vehicle drives away before he gets close enough to read the plate. Then they try harder, usually calling a neighbor down the road, depending on cattle or property loses. He might have occasionally seen a car come up behind him, slow to his speed, then speed on by. All they wanted was the plate number for the sheriff. If the plate was that of a parolee he will get a visit looking for stolen items. If the farmer checks and anything is missing the vehicle owner will get a visit.
I have been in the business of protecting property or people for a long time.
At various times in my life I have been the person rushing to get a license number, description, or any look at what is being loaded in a vehicle.
You can "forget" the stuff about "within 20 feet from a person they can rush you" with a knife before you can draw. If the person with the gun is that slow they better get something else faster. Trainers just want you to practice.
Maybe twice in a deep dark night I had a small handgun that was already in my hand. I also have done numerous other common tricks not appropriate to mention here.
So let me be the first to say "take evasive action". A farmer rushing toward you in broad daylight will not often attack you. A police or security person will not shoot you in the back.
If you are in your vehicle and someone is breaking your window then shoot or drive.
If the photographer was to brandish a gun in that alleged 20 feet, that he may think he "might" be in danger, I know people who are faster than he can imagine, and he just gave them a reason to shoot. Stepping quickly toward a person is not against the law.
I do not know anyone who pulls a knife from 20 feet away. They wait until they are in arms length. Again "stand your ground laws" sound nice, and are legal. Politely take evasive action and live longer, unless you're a police person. Leave confrontations to the police if you can. They have all those night sticks, stun guns and pepper spray on their belts for a reason.
On your own property - do what you must do, none of my friends or ex-employees ever bothered someone on their own turf.
When called, Police show up at your house in uniform for a reason.