When did the criminal gang formed by someone serving six life sentences at the ADX Florence supermax prison in Colorado?
Gangster Disciples: The Gangster Disciples are a criminal gang which was formed on the South-side of Chicago in the late 1960s, by Larry Hoover, leader of the High Life Supreme Gangsters, and David Barksdale, leader of the Black Disciples. Larry Hoover:  Hoover is currently serving six life sentences at the ADX Florence supermax prison in Florence, Colorado.
the late 1960s