No self defense presumption for a disproportionate use of force. I call this the "take your beating like a man" clause. Zimmerman shot Travon because he was getting his butt whupped. If Travon had pulled a knife or gun that would be a different story. Which reminds me. I wonder how this would be playing out in the legal system and the media now if Travon had pulled a gun when he saw Zimmerman pulling his and killed Zimmerman? That would arguably be a better self defense claim. But would Travon now be facing murder charges as a young black male who killed a neighborhood watch captain?
I agree with everything you said except for the above quote.
In matters of self-defense I think claims of disproportional defense should face a very high barrier. I'm not going to go so far as to say it should NEVER be a relevant argument but very rarely I think.
People die all the time from getting hit with one wrong punch or a punch that knocks them out and sends them head-first into the pavement, etc. I know (knew) people who have died in exactly this way. And even when not fatal, people can be very seriously injured in weapon-less physical fights.
More importantly, let's say I'm the one being attacked and I believe my likely injuries will be limited to a broken rib or something minor like that. If I have the ability to prevent someone from breaking my rib by using lethal force, I should have every right to take such action. If my assailant's rationale is that he's willing to attack me using non-lethal violence on the grounds that he's willing to suffer injuries, but he's not going to use lethal threat of violence because he doesn't want to risk death -- well that's just bunk, because *I* would prefer not to be attacked at all!
In my view any individual who initiates any level of violence against another person loses the right to decide how that violence is escalated.
On the same note, I think the punishment for physical assault, even when it doesn't result in serious injuries, should be closer in line to the punishment for murder/manslaughter. I think it's a flaw in the way society thinks about the importance of liberty that, for example, they don't think decking someone in the face is a serious crime, especially if it doesn't result in serious injury.
In my view when you initiate violence, 99% of your "crime" is violating the principle, only 1% is the actual level of carnage that results from your aggression.