Let's pick this story apart.
rating firms’ unholy alliances with the people they rate have been widely exposed, not least by the Securities and Exchange Commission and Congress, which released a pile of damning documents last year.
Even before then, the situation was no secret. CalPERS states in its lawsuit that in 2005 Moody's pocketed $715 million, or 41% of its revenue, from rating "structured" investments. The pension system didn't have to dig deep for this news: It's in the Moody’s annual report.
How about the issue of what CalPERS knew or didn't know about the assets held in the pools? CalPERS says "no amount of diligence" could have given it "actual knowledge" of what the pools contained.
This is slicing the baloney pretty thin. CalPERS knew its SIVs held mortgage assets. It knew that a bank's incentive would be to keep good mortgages on its balance sheet and dump the rest -- say, by offering them to an SIV.
In July 2007, a JPMorgan analyst reported that Cheyne Capital Management, the sponsor of one of the CalPERS pools, had the highest known concentration of real estate assets in the business. If JPMorgan knew, how come CalPERS didn't know?
More fundamentally, why would CalPERS put any money into an investment pool whose defining characteristic is that its investors can't know what it owns?
Many investors and financial analysts figured out the truth about these shady credit evaluations. The e-mails released by Congress and the SEC feature numerous investment executives telling Moody's and its cousins in mid-2007 that they didn't trust their ratings on exotic paper -- conclusions that had plainly originated months earlier, conceivably by late 2006.
Yet CalPERS claims to have been blindsided by the wave of credit downgrades the firms issued on the pools after mid-2007. It was then too late to extricate itself, as all three of its pools were headed for extinction.
The rating firms' complicity in the mortgage and financial meltdowns is a scandal -- that's true. But big investors including CalPERS played along.
They reasoned that no one would care that they had outsourced their due diligence to raters in cahoots with the ratees, as long as everyone was making money. If the money machine stopped, they figured, the rating firms would be convenient whipping boys.
The CalPERS lawsuit pulls the curtain back on this charade. Sure, CalPERS was a victim. The pension fund says it doesn't think the rating firms should be allowed "off the hook" and says it has "a duty to recover losses on behalf of our beneficiaries." But its case reminds me of a line by the great Russian author Nikolai Gogol: "There's no point blaming the mirror if it's your own mug that's crooked."
Michael Hiltzik's column appears Mondays and Thursdays. Reach him at firstname.lastname@example.org, read previous columns at www.latimes.com/hiltzik, and follow @latimeshiltzik on Twitter.