Even if he was the initial aggressor, once he backed off, that does not let the other person go ahead and attack him. Nor does it mean he then has no right to defending his life. Had both backed off, nobody would be dead. Carrying a gun does not create a need for self defense. That need was created by Martin following through with his attack, which is inline with his nature although my understanding they won't allow that submitted as evidence to the jury. As well, the police officer testified that it is not against the law to approach someone and ask what they are doing. Calling that an aggressive attack is not inline with the law.