Many of the country's largest banks received $6 billion in kickbacks from mortgage insurers over the course of a decade, according to a previously undisclosed investigation by the Inspector General of the Department of Housing and Urban Development.

In exchange for the their business, companies such as Citigroup Inc, Wells Fargo & Co, SunTrust Banks Inc. and Countrywide allegedly required reinsurance partnerships on generous terms that violated the Real Estate Settlement Procedures Act, a 1974 law prohibiting abusive home sales practices.

During a two-day presentation in the summer of 2009, HUD's team presented DOJ attorneys with a thick binder of evidence that major banks had engineered a decade-long kickback scheme