I’ve seen that. The results were inconclusive, according to published standards. Aside from that, there was, of course, an eyewitness who both saw and heard Zimmerman screaming, and said so publicly before any of the publicity surrounding this case. I’m not sure how examination of the recording trumps that.
According to published standards, it is inappropriate to draw any conclusion. Insufficient evidence. There shouldn't be ANY expert opinion, beyond that it is not possible to form an opinion from the evidence provided.
That said, this is the family's expert, opining outside of court. Their counsel is in the process of trying the case in public. Crump is just another race-baiter.
Incident like this one its likely both parties were screaming at one time or another. From the wounds on Zimmermans head it would seem to support he was at the disadvantage at one point. When the kid saw the gun he had every reason to scream.
If you’ve ever been in a fight where theres no control like people around to break it up,where neither side really understands the capabilities of the other,theres plenty of grunting groaning and the occasional scream.
End of the day however who knows what happened in this circumstance.