"When Freddie Gray was arrested for possessing an 'illegal knife' in April 2015, he was, by eyewitness accounts that video evidence later confirmed, treated 'roughly' as police loaded him into a vehicle. By the end of his trip in the police van, Gray was in a coma he would never recover from. In the wake of a long history of police abuse in Baltimore, this killing felt like a final straw--it led to a week of protests and then five days described alternately...