The Justice Department's efforts to reach a settlement with Standard & Poor's Rating Services about the ratings provided to mortgage bonds leading up to the financial crisis have failed, and it appears that civil charges will be filed by the Justice Department and state prosecutors. See S&P says it expects U.S. civil suit over mortgage bond ratings, New York Times (Feb. 4, 2013).
The suit is expected to be brought in California and focus on about 30 collateralized debt obligation deals (commonly known as "CDOs") executed in 2007 at the height of the mortgage bubble. The Justice Department has apparently seen "troves" of damaging emails among S&P employees.
S&P claims the suit is meritless, using hindsight to pinpoint a cause that wasn't understood at the time. McGraw-Hill, S&P's parent company, lost 14% of its value after the announcement.