the gunshot, did mr. zimmerman have any other options? >> based on my knowledge and understanding of him, the environment, situation, totality of everything, i don't believe he did. >> dennis root, a so-called expert for the defense on the use of force told the jury zimmerman had no choice but to use his gun against trayvon martin. does it add up to manslaughter, murder or none of the above? >> my let me ask my guests here. tom mesereau, this is a crucial thing i think which is what directions will this jury be given in terms of the potential things they could convicton? because i think there is a general sense that second-degree murder hasn't been established beyond a reasonable doubt but manslaughter, aggravated assault and others possibly could have