. >> in the summer 2014 erik garner was killed after being placed in a choke hold by new york officersding my business officer. please just leave me alone. >> and his haunting final words. >> i can't breathe. i can't breathe. >> i can't breathe, i n cat breathe. >> repeated in ashville. the new york officer was never indicted by a grand jury though still faces federal civil rights charges. a month later 18-year-old michael brown killed in ferguson by officer wilson and grand jury refused to indict and family septemberled with the city for $1.5 million. 2015 in baltimore 25-year-old freddie gray was killed while riding around unsecure in the back of a police van after a jury trial those six officers never held responsible. >> those deaths along with so many others set off protests across the country raising a national conversation on policing in a system that seems to treat people of color differently. >> well, historically the police seem institution arose out of slave catchers. >> for this lieutenant of the san francisco police department the problem in the police force runs deep. >>