Why SEC Employees Are Freakishly Good Stock Traders
...The academics, Emory University professor Shivaram Rajgopal and Georgia State University accounting Ph.D. candidate Roger M. White found that SEC employees tend to sell a company's stock before the SEC takes enforcement action against the company.

The result, they wrote, were abnormal returns of about 4 percent for the market in general, and about 8.5 percent for the U.S. stock market. That's significant. While an SEC employees' stock purchases are normal, their stock "sales appear to systematically dodge the revelation of bad news in the future," according to the paper's findings....