Nine months have passed since President Obama installed John Koskinen as IRS Commissioner, charged with unearthing the agency's targeting scandal and restoring its credibility. It's about nine months past time to acknowledge that Mr. Koskinen is the problem, not the answer.

The 75-year-old former Fannie Mae executive on Wednesday put in another superficial appearance before House investigators, spent another two hours dodging questions, jabbing at investigators, and excusing the misdeeds of the least-trusted organization in America. This from the guy brought in to clean up the mess—a man presented in confirmation as a "turnaround artist" and "reformer."

The Koskinen fail is now becoming a central political focus, as Republicans and even some Democrats question his tenure. Mr. Obama had declared him someone who "knows how to lead in difficult times, whether that means ensuring new management or implementing new checks and balances." Where are the sweeping changes? Where's the accountability? When the best the IRS commissioner can promise America is that "whenever we can, we follow the law"—we're in worse shape than nine months ago.

The only thing Mr. Koskinen has seemed remotely interested in turning around is his agency's ugly story-line. He has yet to even accept his agency did anything wrong, spending a March hearing arguing that the IRS didn't engage in "targeting" and claiming the Treasury inspector general agreed. This was so misleading the Washington Post gave Mr. Koskinen "three Pinocchios, " noting the IG had testified to the exact opposite.

Under his management, the agency has ignored and strung out congressional demands for documents and witnesses. Mr. Koskinen waited months to tell Congress the IRS had "lost" the emails of Lois Lerner, the former IRS official at the center the probe, and arguably only did so because an outside lawsuit revealed that the email record was incomplete. He testified that there were no backup tapes with Lerner emails, but we have since learned there are 760 server drives that may contain copies.