Why Wall Street’s Leaders Escaped Prosecution

Frontline producer and correspondent Martin Smith talks about his investigation into why the U.S. Department of Justice has failed to act on credible evidence that Wall Street knowingly packaged and sold toxic mortgage loans to investors, loans that brought the U.S. and world economies to the brink of collapse. Frontline’s documentary “The Untouchables” includes interviews with top prosecutors, government officials and industry whistle-blowers, and reports allegations that Wall Street bankers ignored pervasive fraud when buying pools of mortgage loans. “The Untouchables” airs January 22, at 10 p.m., on PBS.