One question that keeps sticking around: How did Goldman Sachs manage to get out of the building before it burned down? One answer -- it sneaked out the back door while no one was paying attention.

McClatchy reviewed hundreds of documents, SEC filings and other material to piece together the story on this. Read the entire article here. The basics: In 2006 and 2007, Goldman sold more than $40 billion worth of securities that were backed by subprime mortgages. Goldman just didn't tell the people buying the securities that it was secretly betting against those loans:

"The Securities and Exchange Commission should be very interested in any financial company that secretly decides a financial product is a loser and then goes out and actively markets that product or very similar products to unsuspecting customers without disclosing its true opinion," said Laurence Kotlikoff, a Boston University economics professor who's proposed a massive overhaul of the nation's banks. "This is fraud and should be prosecuted."

The courts will get a shot at this. Several pension funds and other institutional investors have sued Goldman:

Mississippi Attorney General Jim Hood... assailed the investment banks "who packaged this junk and sold it to unwary investors."

California's huge public employees' retirement system, known as CALPERS, purchased $64.4 million in subprime mortgage-backed bonds from Goldman on March 1, 2007. While that represented a tiny percentage of the fund's holdings, in July CALPERS listed the bonds' value at $16.6 million, a drop of nearly 75 percent, according to documents obtained through a state public records request.

At Clusterstock, John Carney argues Goldman wasn't keeping any secrets:

Goldman's top economist was warning about the housing market way back in 2005. In reaction to a study published by two academics in the Wall Street Journal that purported to show there was no housing bubble, Hatzius authored a note titled "Bubble Trouble? Probably Yes."

It was written in the same cautious language of most of these Wall Street economists notes but it's message was unmistakable: house prices are over-inflated and due for a serious decline.

That hardly addresses the issue of whether Goldman was selling a product it knew was garbage in order to make a killing on its inevitable rotting. I'd like to know what kind of legal protection Goldman put in its prospectus, and whether that'll hold up in court.

But the pension funds and the rating agencies share some of the blame here. No one forced pension funds and other similar investors to ramp up their risk exposure by seeking out higher returns. At the same time, they probably didn't think there was much risk because these trash collections were rated AAA.

In McClatchy's story, Duke law professor points out another problem:

Cox said that existing laws, however, don't require sufficient disclosures about trading, and that the government would do well to plug that hole.

Either there are rules in place to protect investors or there aren't. In the latter case, if you decide to wade in, you best assume sharks are in the water.