Trayvon Martin Case Evidence Photos

This Feb. 27, 2012 photo released by the State Attorney's Office shows George Zimmerman, the neighborhood watch volunteer who shot Trayvon Martin, with blood on the back of his head.

This Feb. 27, 2012 photo released by the State Attorney's Office shows George Zimmerman, the neighborhood watch volunteer who shot Trayvon Martin, with blood on the back of his head.

This Feb. 26, 2012 photo released by the State Attorney's Office shows a yellow evidence marker points to a single bullet casing from the Kel-Tec PF-9 9mm handgun used by George Zimmerman, the neighborhood watch volunteer who shot Trayvon Martin.

This Feb. 27, 2012 photo released by the State Attorney's Office shows George Zimmerman, the neighborhood watch volunteer who shot Trayvon Martin, with blood on the back of his head.

FILE - This undated file family photo shows Trayvon Martin. The Sanford police department released a video Thursday, March 29, 2012, showing George Zimmerman being escorted into the Sanford police station in handcuffs on Feb. 26, 2012, the night he fatall