Before the controversial police killings of young African Americans last year, Black Lives Matter had its roots in the slaying of the Florida 17-year-oldWhen 17-year-old Trayvon Martin was gunned down three years ago this week in Sanford, Florida, his tragic death breathed life into a dormant civil rights movement.While many associate the Blacks Lives Matter movement most closely with the fatal shooting of Michael Brown in Ferguson, Missouri, in many ways it was Martin’s death that first inspired a new generation of activists to take to the streets and protest against a system they felt held the lives of African Americans in small regard and was in desperate need of legislative change.