There is nothing to argue.
The defense has every right to subpoena Trayvon Martin's school and social media records and to use them to rebut the prosecution's claim that TM was just going to the store for Skittles and Tea for his little bro when they were actually the ingredients for a street concoction that he enjoyed and that had probably caused the degradation of his liver at his young age as is found in his autopsy report.
The defense has every right to subpoena those records to rebut the prosecution claim that TM was not the aggressor that night with evidence that he enjoyed MMA fighting.
The defense has every right to rebut the family's claim that TM was a good student on his way to airline pilot training by pointing out that he had missed 53 days of school over 6 months and was suspended 3 times and that his grades had suffered because of it.
The defense has every right to rebut the image that TM was a 12 year old looking cherub at the time of his death with pictures from his facebook and twitter accounts that show him as a older teenager with a thuggish gangsta appearance that he relished.
The defense has every right to rebut the saintly innocent good student image of Trayvon with the reality of his school suspensions, vandalism, marijuana possessions, truancies, possession of jewelry that was not his, and whatever else the chum brings to the surface.