Obviously, an audit would hurt somebody
Via Reuters:
Federal Reserve Chairman Ben Bernanke said on Friday congressional proposals to audit the Fed and strip it of regulatory powers as part of post-crisis reforms could damage prospects for economic recovery and financial stability going forward.
"These measures are very much out of step with the global consensus on the appropriate role of central banks, and they would seriously impair the prospects for economic and financial stability in the United States," Bernanke wrote in a column posted on the Washington Post's website.