By evaluating the evidence, and going where the facts lead us, not where we want them to go.
If you are trying to choose between scenarios in which either Zimmerman or Martin physically assaulted the other, and there is no direct evidence indicating who assaulted whom, the next best thing to do is examine their personal histories and look for evidence one or the other or both were likely to resort to violence. There are certain facts in evidence that speak to the matter, and we can directly compare them.
Facts in Evidence:
In 2001 Zimmerman was involved in a fight in Virginia that resulted in police being called and the matter going before a court of law. We know almost nothing about the fight - who started it or why, whether Zimmerman provoked the fight or was an innocent victim. But we do know it happened when he was 17 or 18, and that the court records were sealed.
In 2005 Zimmerman's fiancé sought and was granted a Restraining Order against him. She testified he had become violent over the course of an argument, and that he had struck her in the face on another occasion as well.
Also in 2005, Zimmerman was arrested for felony assault of a police offer after he grabbed a cop and slammed him against a wall when the cop detained and questioned one of Zimmerman's friends for underage drinking. Zimmerman later claimed he thought the guy was a bouncer. The charge was reduced to a misdemeanor as part of a plea deal, and later waived upon Zimmerman's successful completion of an alcohol education program.
Facts in evidence regarding Martin's encounters with the law: there are none. Martin's only known run-ins with authorities of any sort are his four suspensions from school. All four incidents were handled at the school level. His transgressions were:
1. excessive tardiness
2. writing "wtf" on a school locker
3. fighting
4. having in his possession a baggie containing marijuana residue.
So at this point, an honest evaluation of the facts leads us to favor Zimmerman as the aggressor, since Zimmerman is the one with the documented history of being aggressive. Even if we suppose Martin was the aggressor in his fight at school (and we have no reason to suppose this), the level of violence did not lead to police involvement or court action, as teenaged Zimmerman's fight and adult Zimmerman's violence did.
Allegations:
A former co-worker of Zimmerman's told the police that he once saw Zimmerman pick up a drunk woman and throw her down onto a sidewalk. He also said Zimmerman could be a nice guy at times but when he lost his temper he became violent. Zimmerman's cousin told the police that Zimmerman assaulted, bullied, and sexually molested her for 10 years starting when she was 6 years old. She also said Zimmerman became violent when crossed.
Allegations made against Martin by first hand witnesses or people with direct knowledge of events: none. Not one of Martin's neighbors, teachers, schoolmates, family members, camp counselors or administrators has ever alleged Martin committed an act of violence, other than the reported school fight.
So at this point an honest assessment of the evidence leads us toward the conclusion that Zimmerman was more likely to have resorted to violence, and Martin less likely.
Now, there have been any number of unsupported assertions, wild speculations, and scurrilous gossip about both Zimmerman and Martin. The overwhelming majority of them are strongly anti-Martin. They are also notably racist, as is the line of argument that denies Martin the same right of self defense that Zimmerman is granted. But their most important characteristic is the lack of any evidence whatsoever to support them. They are all "what if...?" stories and blatant fabrications masquerading as evidence, and they should not be allowed to blind us to the known facts.
The known facts are this: on the night Zimmerman and Martin met, one of them had a history of aggression and violence, and it wasn't Martin. And at this point in time, with Zimmerman's continuing pattern of aggression and violence, I cannot understand why Martin is still being vilified and Zimmerman still enjoys the benefit of the doubt.
