On February 26, 2012, Trayvon Martin, 17, was shot and killed by 28-year-old George Zimmerman, the self-appointed neighborhood watch leader at the Retreat at Twin Lakes, a gated community in Sanford, Fla. Zimmerman was initially questioned by the Sanford Police Department, but he claimed self-defenese under Florida's "Stand Your Ground" law, and was released without being charged. Within three weeks, the story went national, sparking outrage that an unarmed teenager had been killed without anyone being charged with the crime. After intense pressure, Zimmerman was charged with second-degree murder last April. The trial begins today.

Over the past 15 months, Trayvon Martin's killing has become a lightning rod for issues of race, crime, self-defense, and even gun control. This timeline highlights the most significant moments of the case in chronological order, and tracks the shifting media coverage and public opinion.

Written by Julian Kimble (@JRK316)

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