Twitter CEO Jack Dorsey and civil rights activist DeRay Mckesson talk with Recode's Peter Kafka about how Twitter can both help and hurt political causes such as #BlackLivesMatter. Dorsey acknowledges that Twitter has often failed to prevent abuse and says he's trying to help it reach its full potential without compromising users' safety. The two talk about their sometimes conflicting opinions of how Twitter should grow, and Mckesson pitches his ideas for applying social media to protests, which he calls "telling the truth in public."