Outrage!

Some senior staff at Moody’s Investors Service were aware in early 2007 that constant proportion debt obligations, funds that used borrowed money to bet on credit-default swaps, should have been ranked as much as four levels lower, the Financial Times said, citing internal Moody’s documents. Moody’s altered some assumptions to avoid having to assign lower grades after correcting the error, the FT said. - Bloomberg.

I don't know how I missed the part in bold earlier. This goes beyond lawsuit. There is only one word for this: prison.