If Fitch, Moody’s and other credit rating companies committed fraud, why are they not held criminally liable?

Great question, CNBC did a 2 hour special about this called "House of Cards." I'm not sure why they have not been held accountable for what they did. They claim that had complex mathematical models that clearly showed these bundled mortgages could not fail.

negligence is a crime, think of child negligence laws. However, specifically related to your question, the crime could only be produced with willful intent to committ fraud. There is a fudiciary responsible they have in serving the common good of the public by providing correct information; however, it is up to the consumer to make a decision based on the information, the liability is held in the decision of the consumer, not the means by which they made thier decision, at the very least, it could pose as misrepresentation, but with nothing to gain from it from fitch and moody, highly unlikely.

Your question is incoherent.

First off, negligence is not a crime.

Do you have any evidence that Moody's or any other credit agency knowingly published false data with an intent for consumers to rely on it? If you do, call the US attorney.

If you don't, well, then there is the answer to your question.