I'm Brooke Gladstone. This week, a mistrial was declared in the case of Michael Slager, the white police officer who shot unarmed black man Walter Scott in the back as he ran from a traffic stop. Scott's death was caught on a passerby's phone.

Slager's original testimony that Scott grabbed his taser and was threatening him

fell apart when the video surfaced. In it, Scott is clearly seen running away while Slager takes

aim and... It's been three years since the social movement Black Lives Matter came into being.

Its protests of police killings of unarmed black people has put the group at odds with police unions, incoming President Donald Trump.

When you're calling death to police and to kill the police, essentially, which is what they said,

that's a real big problem.

And the likes of Rush Limbaugh.

They're a terrorist group.

They're quickly becoming a terrorist group committing hate crimes.

This summer, the White House rejected a petition signed by more than 141,000 people,

urging it to formally recognize Black Lives Matter as a terrorist group.

Given the news this week of the mistrial, we thought we'd replay our July interview with Patrice Cullors,

a co-founder and leading voice in the Black Lives Matter movement.

We spoke to her after the deaths of five police officers at the hands of a black sniper in Dallas

at a Black Lives Matter protest. I asked for her reaction to Milwaukee's Black County Sheriff

David Clark's remarks on CNN.

This anti-cop sentiment from this hateful ideology called Black Lives Matter has fueled this rage against the American police officer.

Our movement has never called for the execution of law enforcement. Never. Yet many want to

place the blame at our feet. There is a historical legacy of undermining

black communities who stand up and fight for our right to really be a part of this American

democracy. So tell me what Black Lives Matter does advocate.

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