This LA Times article goes into some of the details of the Bush/Harken SEC investigation. While it leaves a lot of questions unanswered, it's largely exculpatory.
High Finance Run Amok [latimes free reg req] is a Kevin Phillips editorial on the "financialization" of the US economy. "As the financial sector, in short, became too important to fail, the Fed and the Treasury abandoned market economics to embrace socialization of credit risk. No other sector of the U.S. economy, save possibly defense, received such governmental assistance."