Josh Marshall summarizes my own view very well:
If you’re a wannabe cop loser with a gun who starts stalking a kid in the dark, you’re responsible for the outcome.
I blogged pretty much the same thing back in April 2012, and my opinion is not changed now:
In my mind, Zimmerman is guilty. Not because I know how the specifics played out, that Martin did not assault him, or anything else. Instead, it was because Zimmerman was the one holding a gun, he did not need to pursue Martin (the 911 call made that clear), and so he bore responsibility.
Too many Americans have too cavalier an attitude about what it means to carry a gun—essentially, “I’m packing so don’t frack with me.”
There’s a reason why we ask professionals to take care of law enforcement, and reasons why cops train long and hard for it. Zimmerman had not been through this. There are damned good reasons why even a late response time from cops is better than grabbing your gun and taking care of things yourself.
But this was not even that. Zimmerman was not defending his home. He was not even “standing his ground”—you cannot stalk someone and chase them and then claim you were “standing your ground.” He was, in fact, instructed to hold back, and not for no reason.
He defied the instructions from authorities, violated the principles of armed confrontation, and had he not done these things, Trayvon would have had his Skittles and iced tea and Zimmerman would have finished his trip to Target. It was Zimmerman’s gross misconduct which caused the death.
That’s my take, at least.