Assistant state attorney John Guy uses a foam dummy to describe the altercation between George Zimmerman and Trayvon Martin to defense witness and law enforcement expert Dennis Root (R) during Zimmerman's trial in Seminole circuit court in Sanford, Florida July 10, 2013. Zimmerman has been charged with second-degree murder for the 2012 shooting death of Trayvon Martin. REUTERS/Gary W. Green/Pool (UNITED STATES - Tags: CRIME LAW)