Opinion | Americans Must Know if Their President Is a Crook

Third, while not often discussed in the current tax return controversies, it has been Internal Revenue Policy for decades to conduct a mandatory annual audit of presidential returns. A reform law should mandate that, once the I.R.S. has completed these audits, it release them to the public.

Fourth, the Office of Government Ethics, which administers the Ethics in Government Act financial filing requirements for the executive branch, should have the responsibility of managing tax return disclosure law. It would work with the president and vice president (and candidates subject to the requirement) to ensure that it has received a completed filing for public release and it should be authorized to consult with the I.R.S. for this purpose. The law should also provide that if a president balks, then the Joint Committee on Taxation should be authorized to demand the returns from the Treasury secretary and, if necessary, to sue for enforcement in federal court.

A reform along these lines is consistent with the Constitution. Courts have long upheld personal financial disclosure requirements imposed on public officials. The Supreme Court has noted that presidents’ privacy rights are strongest when asserted “in matters of personal life unrelated to any acts done by them in their official capacity.” The vast powers that president wield, including their administration of the tax laws, leave little doubt about the relevance of their personal tax affairs to their official duties and to the objective of deterring corruption. The disclosure norm that Mr. Trump disregarded spoke powerfully to the public interest in this tax information.

Moreover, this history refutes any suggestion, rooted in a concern for the separation of powers, that tax return disclosure interferes with presidents’ performance of his or her constitutionally assigned functions. It is true that Trump’s refusal to release his personal tax returns incited a battle that has proved costly to his presidency. But the fault for the damage done lies in Mr. Trump’s rejection of the longstanding transparency norm. As the historian Arthur Schlesinger wisely suggested years ago, a “strong presidency” is one conducted “within an equally strong system of accountability.” Mr. Trump has fought this accountability and has not made the presidency stronger in doing so.

Although the Trump tax cases addressed complex constitutional issues, they are defined in the public mind and debate by something simpler: the struggle over access to his tax returns.

And, on that question, only Congress can do by legislative reform what is required to protect an interest in this information that is deeply implicated in but still separate from Congress’s or a prosecutor’s: the interest of the public.

Bob Bauer, a professor of practice and distinguished scholar in residence at New York University School of Law, was a White House counsel in the Obama administration and is a co-author, with Jack Goldsmith, of the forthcoming “After Trump: Reconstructing the Presidency.”