OFFICIAL: Goldman Sachs not uniquely bad apple.

Whether various US and EU investigatory agencies ultimately get that many banks in the Dock for skullduggery during the Sub Primaries of 2008, it’s already clear that there are many villains to have a crack at.

One firm that was a major player in mortgage securities, Deutsche Bank AG, illustrates a pattern investigators are looking at. While creating and selling mortgage securities to some of its clients, the big German bank was not only advising other clients to bet the other way, but also sometimes doing so itself.

Deutsche’s two-faced dealings with one investor client in 2007 illustrate how it played both sides of the mortgage-securities market. At a time when the U.S. housing and mortgage markets were beginning to crack, Deutsche was putting together bond deals backed by subprime mortgages. The allegation is that DB knew the backing was very poor quality.

The M&T Banking Corporation of Buffalo poured $82 million into the resultant Deutsche deal, known as Gemstone VII. Within 10 months, M&T lost 98% of its investment, according to a lawsuit it has filed against the German major.

So when somebody gives you the ‘it’s only a small minority’ line, give them the bum’s-rush. And don’t forget that Deutsche is one of the bank under the spotlight for not declaring its sovereign debt liabilities.

There’s a hard, a hard, a hard rain gonna fall.