Exactly what happened during that 2:32 gap only Zimmerman has survived to say.

Knox does not know exactly when the struggle began -- because that moment was not recorded -- but it had to come some seconds before the 911 call was made. It took some time for the 911 caller to hear and react to the struggle and then make a decision to get to a phone and properly connect with 911.

Knox also does not speculate on who may have been the initial aggressor, or whether either person had a right to fight back with deadly force.

"What you have here is a case where you have two people perceiving one event in two very different ways," Knox concluded. "George Zimmerman is perceiving that Trayvon Martin is a suspicious character, he's doing something wrong. Trayvon Martin perceives it as, 'Why is this guy following me? Why is he staring at me?' What can happen in a situation like that is each person's individual perception causes them to act in a particular way. Their actions collided and turned into this tragic event."