Some apparent facts here

http://en.wikipedia.org/wiki/Shooting_of_Trayvon_Martin

I have done a little more digging and it seems most probable that

1. Trayvon Martin had no prior record of being charged or convicted of criminality
2. Zimmerman had at least one previous record for assault.   Public records show he was arrested in Orange County in 2005 on charges of resisting arrest with violence and battery on a law enforcement officer. The charges were later dropped. His neighbourhood watch activities had sparked complaints from residents. The tapes of calls seem to record him calling Martin a "fucking coon".
3. The policeman who initially refused to arrest Zimmerman, Sergeant Anthony Raimondo in 2010,declined to arrest Justin Collison, who brutally attacked a black homeless man, leaving him unconscious and breaking his nose. Collison, who is white, is the son of a Sanford police officer and the grandson of a former Florida judge. Collison was intoxicated at the time of the unprovoked attack. Also, a Youtube video captured the attack while it occurred. Despite having possession of the video, Raimando still refused to arrest Collison. Police only arrested Collison after the national media released the video and criticized police handling of the case.


At the moment I find it hard to envisage a clearer case of a racially motivated pursuit and murder - a case of "walking whilst black". How Zimmerman could pick on Martin, chase Martin, and shoot the unarmed Martin and still claim that he reasonably thought he was acting in self defence is wholly baffling even under the fairly ridiculous and ill drafted and thought out Jeb-Bush signed "stand your ground" local law.

That law however does make a good case for federal pre-emption to create a US wide consistent law of homicide.