One is the SEC's investigation, specifically into the US downgrade. Which I agree looks fairly sad and isn't really going to restore anyone's confidence in the US' credit rating... they just have appearances against them, even if it should turn out S&P really did violate its normal procedures on this one.

And then there's the Justice Department's one that had been going on for longer. There may be something in what you say about the timing of that news leaking out, obviously, but whether it ultimately hurts S&P will depend on the result of the investigation - and I don't really believe the US downgrade will influence that result. If they hadn't downgraded and the Justice Department had still found them guilty at some point down the line, that would've come to the light fast enough.

The rating agencies are going to take hits one way or another, and not without reason, but I think you're rather exaggerating when you say "destroyed", or suggesting S&P will be taken on much harder than Moody's and Fitch.