So running around without any type of training is ok? I think not. Basic laws on probable cause should be taught, if your going to try an follow someone you think is a suspect in a crime.
At the time z followed m no life or property were in harms way. So what gave him the right to pursuit or even investigate the suspected person?
Could it have been that m taught it was another homie trying to harm him that night? If he was a thug that wouldn't be hard to understand that someone who try and harm him. Due to black and black crime happening daily.
I'm not an officer, but I'm pretty sure exhibiting really strange behavior in a high crime area is grounds for reasonable suspicion. I also know that turning away from an officer and walking away "nervously" has been upheld as a valid reason for a stop. That said, Zimmerman wasn't stopping anyone, he needs no right to peruse as he has a right to travel.