The New York Police Department puts an endless list of tasks on the shoulders of its so-called white shirts — the commanders atop an army of lesser-ranking officers in dark blue...“Unlike much street policing, large marches and protests involve lots of advance planning and the assignment of many supervisors to the scene,” said Christopher T. Dunn, of the New York Civil Liberties Union. “It’s therefore not surprising that supervisors would be personally involved in arrests. What is surprising and alarming is the sight of them using excessive force against protesters. Beyond the injuries that causes, it sends a terrible message.”