… , a leader of the American Indian Movement (AIM), is serving … law enforcement provocations against Native Americans that reached a high … , became active in Native American social and political causes … Blackhorse, by the Royal Canadian Mounted Police at the …… , a leader of the American Indian Movement (AIM), is serving … law enforcement provocations against Native Americans that reached a high … , became active in Native American social and political causes … Blackhorse, by the Royal Canadian Mounted Police at the …