"US senators' personal stock portfolios outperformed the market by an average of 12 per cent a year in the five years to 1998."
Other facts from the study, by Georgia State's Alan Ziobrowski: (1) Junior senators did even better, earning excess returns of 20% per year. (2) The gains come from uncanny purchases, not prescient sales. (3) There was no difference in performance between Democrats and Republicans. No surprise there.
Here's the story. You be the judge.