Frontline’s “The Untouchables” investigates the lack of prosecutions of Wall Street executives after the 2008 financial meltdown, shedding light on the intricacies of economic regulation and justice.

More than four years since the financial crisis, no senior Wall Street executive has faced criminal prosecution for fraud. Are Wall Street executives “too big to jail”?

In The Untouchables, premiering Jan. 22, 2013, at 10 P.M. on PBS (check local listings), FRONTLINE producer and correspondent Martin Smith investigates why the U.S. Department of Justice (DOJ) 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.

Through interviews with top prosecutors, government officials, and industry whistleblowers, FRONTLINE reports allegations that Wall Street bankers ignored pervasive fraud when buying pools of mortgage loans. Tom Leonard, a supervisor who examined the quality of loans for central investment banks like Bear Stearns, said bankers instructed him to disregard clear evidence of fraud. “Fraud was the F-word, or the F-bomb. You didn’t use that word,” says Leonard. “By your terms and my terms, yes, it was fraud. By the [industry’s] terms, it was something else.”

Former Sen. Ted Kaufman (D-Del.), appointed to fill Joe Biden’s long-held Senate seat when he was sworn in as vice president in January 2009, was determined to see bankers in handcuffs. “I was upset about what went on on Wall Street that brought about the financial crisis,” Kaufman recalls. “That doesn’t happen if something bad isn’t going on.”

Yet Kaufman left office in late 2010, frustrated by the lack of criminal prosecutions. Jeff Connaughton, Kaufman’s chief of staff, remains convinced that the DOJ failed to prioritize prosecuting Wall Street. “You’re telling me that not one banker, executive on Wall Street, or player in this entire financial crisis committed provable fraud?” asks Connaughton. “I mean, I just don’t believe that.”

Smith asks Lanny Breuer, assistant attorney general for the DOJ’s Criminal Division, about his failure to criminally indict Wall Street executives. “I think there was a level of greed, a level of excessive risk taking in this situation that I find abominable and very upsetting,” says Breuer. “But that is not what makes a criminal case.”

Critics disagree, including two high-level sources within Breuer’s division and former New York Attorney General Eliot Spitzer. “They have not done what was needed,” Spitzer says. “The greater risk is that corrupt behavior that is damaging to our economy, that leads to something as enormously painful as the cataclysm of ‘08, goes unaddressed.” 

New York Attorney General Eric Schneiderman finally filed a significant lawsuit against JPMorgan Chase and Bear Stearns in 2012. It closely mirrors claims first made by private plaintiffs almost two years earlier. Despite strong evidence of fraud, the government again decided not to pursue criminal charges. Meanwhile, banking scandals continue to surface almost weekly. 

The Untouchables is written and produced by Martin Smith. Co-producers are Linda Hirsch and Ben Gold. The deputy executive producer of FRONTLINE is Raney Aronson-Rath. The executive producer of FRONTLINE is David Fanning.