Former Goldman Sachs trader Fabrice Tourre (Photo by Peter Foley/Getty Images)

Correction, 4/8/2014, 10:00 a.m. EDT: An earlier version of this story said that Fabrice Tourre is appealing his civil fraud verdict. He has not yet announced if he will appeal. The 21st paragraph of the story has been revised to reflect this correction. We regret the error.

One of the continuing criticisms of the U.S. Securities and Exchange Commission is that it is not a fearsome regulator. It didn’t sue the top executives on Wall Street whose actions led to the financial crisis, and it still shows little appetite for targeting the most powerful people at the big financial institutions. In the agency’s most emblematic case arising from the crisis—its 2010 lawsuit against Goldman Sachs & Co. over the Abacus 2007-AC1 investment vehicle—the SEC pursued a low-level vice president and no one higher. The question persists: Why?