Every year about four percent of the employees working at the Securities and Exchange Commission decide for various reasons to voluntarily leave the agency and seek greener pastures. [Having spent years gaining experience and connections at the nation's top financial regulator, these lawyers, accountants, economists, and others are often in high demand when they return to the private sector. This is particularly true for senior SEC officials returning to private practice.

In better economic times, this so-called “revolving door” of employees moving from public to private sector gets little scrutiny or criticism. When financial markets are rocky, however, and the SEC ...