The Internal Revenue Service headquarters in Washington, D.C. (Andrew Harrer/Bloomberg)

Mark A. Patterson was Democratic staff director and chief counsel of the Senate Finance Committee from 1995 to 1999 and chief of staff at the Treasury Department from 2009 to 2013. He is a partner in the Perkins Coie law firm, which provides legal services to the Clinton campaign; he is a supporter of Hillary Clinton but does not personally represent her campaign.

The debate over Donald Trump’s tax returns overlooks an important point: The lack of any mechanism to require presidential candidates to disclose their returns means that our system holds candidates for the nation’s highest office to a much lower standard than many applicants for lesser federal positions.

Donald Trump's stance on presidential candidates has changed significantly over the years. Here's how. (Peter Stevenson/The Washington Post)

Dozens of nominees to Cabinet- and sub-Cabinet-level positions in the Treasury Department, Social Security Administration, Department of Homeland Security, Office of the U.S. Trade Representative and other agencies are required to submit their tax returns to the Senate, where they are reviewed by the relevant Senate committee, sometimes working with the Joint Committee on Taxation.

Many (although not all) senior federal appointments are subject to this requirement, which is imposed to ensure that people in positions of public trust have complied with the law. There is no exception to the requirement for people who are being audited by the Internal Revenue Service; in fact, nominees are asked detailed questions about any current or recent audits. Regardless of whether a nominee is under audit, Senate committees that require submission of tax returns will not act on a nomination until those returns have been provided and reviewed.

The tax-review process of the Senate Finance Committee, which has jurisdiction over nominations to multiple executive branch agencies, is particularly stringent. The committee requires nominees to submit tax returns for the most recent three years, and if any concerns are identified in those returns, the committee may require the nominee to provide returns covering the past 10 years. The committee staff also conducts interviews of nominees. If the committee determines that a nominee’s taxes have not been paid in full, it offers a choice: The committee can release a public report detailing the noncompliance and require immediate payment of those amounts, or the nominee can withdraw and the committee will keep the tax information confidential.

It makes no sense whatsoever for candidates for the presidency — the office charged under our Constitution with seeing to the faithful execution of the laws — to be held to a weaker accountability standard than subordinate federal officials are. To correct this problem, Congress should act immediately to require public disclosure of tax returns by presidential candidates. And in the interim, if Trump continues to refuse to release his returns, he should at the least submit them to the Senate Finance Committee (which is controlled by Republicans) or the nonpartisan Joint Committee on Taxation for review and a public report on his compliance. If, as he maintains, he has satisfied his tax obligations, he should have nothing to fear from such a review.

Republicans in Congress would presumably support such a move by Trump. Over the past eight years, Republican senators and staff have devoted a tremendous amount of time and energy to scrutinizing the tax returns of President Obama’s nominees. Many of these nominees were required not only to submit multiple years of returns, but also to answer dozens of detailed questions about sources of income, deductions, investments, tax treatment (and immigration status) of domestic employees and other topics. Republican senators who have demanded this information from lesser officials should hold the GOP presidential nominee to at least the same standard of accountability.

Trump told one interviewer that a question about his taxes was “none of your business.” But public disclosure of presidential candidates’ tax returns has been the accepted practice in the modern era, and for good reason. Paying taxes is a fundamental obligation of citizenship, and the public deserves to know whether its next leader has fulfilled this obligation.