Beginning in the late 1960s, the infamous "Black Mafia" terrorized predominantly African-American sections of Philadelphia and was linked to some of the most heinous crimes in Philadelphia history. The organized group, one of the bloodiest crime syndicates in modern US history, collapsed in the late 1980s after several successful prosecutions and internal conflict. Who were Philadelphia's "Black Mafia"? We speak to a former Philadelphia police officer turned Penn State faculty member about his latest book, "Black Brothers Inc.: The Violent Rise and Fall of Philadelphia's Black Mafia". Guest: Sean Patrick Griffin