nightmare to be followed on the way home in the dark by a stranger. isn't that every child's worse fear? that was trayvon martin's last emotion. >> reporter: in every angle and every case of his argument from what we heard it seemed to be an emotional appeal. it was more of an explanation from mark o'mara. it started as a legal lesson explaining what it takes to find a person guilty of a crime and not guilty. he showed charts. he showed that video reenactment he wanted to have admitted as evidence but used as a demonstrative tool. he tried to explain it's not his burden to prove guilt beyond a reasonable doubt.