July 5, 2013 5:51 PM
Trayvon Martin's mother, Sybrina Fulton, took to the stand during the murder trial of George Zimmerman, the man who shot the teenager in a Sanford, Florida apartment complex in 2012. She testified that the screaming voice on the 911 call was Trayvon's. Determining whose voice that was is crucial to the case as it could prove who the aggressor was in the altercation that led to Trayvon's death. Susan McGinnis reports.