The most powerful czar in Washington will receive some long-overdue scrutiny today when the Supreme Court hears a challenge to the constitutionality of the Public Company Accounting Oversight Board (PCAOB).

This board, created by the Sarbanes-Oxley Act of 2002, regulates the auditors of publicly-traded firms. The members are hired by the Securities and Exchange Commission (SEC) and, say the plaintiffs in Free Enterprise Fund v. PCAOB, do not answer to the president. This violates the Constitution's "appointments clause," according to which senior executive-branch officials should be appointed by the president and confirmed by the Senate.

Yet Sarbanes-Oxley, or Sarbox, itself should be subject to scrutiny. New research suggests that the costs of this legislation far outweigh its benefits to the investing public.

If you're wondering whether the members of PCAOB qualify as senior officials, consider that they have regulatory power over every public company in America. Board members fund their activities by collecting taxes, i.e., fees, from public companies based on the size of their assets.

But those fees are just the tip of the iceberg of costs imposed by PCAOB. The board is charged with making sure that Sarbox's Section 404 rules on "internal controls" over bookkeeping are implemented. These rules are so onerous that companies have had to undertake exhaustive investigations of such minor issues as how many people should be required to authorize small customer refunds at a retail location.