I’d think the forensic (gun powder)and autopsy would settle the case. OTOH reports can be manipulated. Pictures ARE worth thousands of words.
Zimmerman's self-defense claim hinges on his being reasonably in fear of serious injury, and, I agree, on a close range shooting. But close range shooting isn't enough on its own. Having his account substantiated with multiple piece of evidence is what gets him the justice he deserves. He was decked, see broken nose. He didn't seek the fight, see call to police. He didn't seek to be arms length from Trayvon, let alone being decked. He was at a physical disadvantage for most or all of the duration of the fight, see eyewitness testimony that has him on the bottom. His head was being bashed, see cuts. He was yelling for help, see eyewitnesses and contemporaneous remark to EMT.
The state has NOTHING in the way of contradictory evidence, except Sybrina's claim that Martin is heard screaming for help. So, who you gonna believe? Sybrina? of the eyewitness +George +George's dad +George's brother (and there is a report that the police asked George to reproduce his scream, and they recorded that reproduction).
Essentially what's going on is a need to disprove a few deliberate, craven liars.