He was told not to follow Martin. He did.
The only real problem is, orders from 911 dispatchers are NOT legally binding in any way whatsoever. I think I posted the link to this story awhile back, but a couple months ago there was a woman who shot and killed an intruder to her house. She was on the phone with 911 and the dispatcher explicitly told her to put the gun down and to not fire and to wait for the police to show up." Eventually the guy busted through the door and she fired. He had been armed. The police showed about 10 minutes after that. She was also not arrested.
Edit: So while the fact that Zimmerman pursued LOOKS BAD on him, it is not necessarily legally relevant. The simple fact of the matter is that it is perfectly legal to follow someone. If Zimmerman simply followed Martin and Martin ended up starting a physical confrontation, then Zimmerman is completely and totally within the bounds of the law.
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SmartMuffin - Because anything less would be uncivilized - http://img.imgcake.com/smartmuffin/barkleyjpgde.jpg
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