george howell joining me live now. this is a significant ruling particularly for the prosecution. they wanted this analysis to be entered, wanted the jury to hear this. why did the judge say no? >> backing up, the prosecution wanted to show george zimmerman as the aggressor in this case. this hurts their case very significantly. when you look at the situation, back on february 26th, several people called 911. there was one phone call that's been highly scrutinized where you hear someone screaming "help, help" in the background. was that trayvon martin? was it george zimmerman? both sides had their own experts explaining their opinions on that. let's listen to the tape so you can hear exactly what we're talking about. >> does he look hurt to you? >> i can't see him. i don't want to go out there. i don't know what's going on. >> they're sending. >> help! >> he is yelling help? >> yes. >> if you're on the defense