by Alec MacGillis ProPublica is a Pulitzer Prize-winning investigative newsroom. Sign up for The Big Story newsletter to receive stories like this one in your inbox. Series: A Closer Look: Examining the News More in this series On Jan. 10, the U.S. Department of Justice released a 123-page report on the 1921 racial massacre in Tulsa, Oklahoma, which claimed several hundred lives and left the thriving Black neighborhood of Greenwood in smoldering ruins. The department’s investigation determined that the attack was “so systematic and coordinated that it transcended mere mob violence.” While it conceded that “no avenue of prosecution now…