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The Trump administration is pushing back against House Ways and Means Committee Chair Richard Neal's (D-Mass.) request for President Trump's tax returns, arguing it serves no legitimate policy purpose. The 1924 law Neal is using doesn't require a policy rationale, though Neal has provided one: monitoring how the IRS audits presidents' tax returns. (The last time Congress checked on a sitting president's taxes, Richard Nixon turned to owe the IRS about $477,000.)

Most tax-law experts agree Neal is on firm legal ground in demanding Trump's tax returns to view in private ("executive") session. Before 1924, "the president had the sole and unconditional right to obtain and disclose anyone's tax return information," University of Virginia law professor George Yin tells Vox. But after the Teapot Dome scandal, Congress decided "it had to have the same access to tax information as the president," to investigate the president and the executive branch.

In fact, "the only thorny legal question arises if the full Ways and Means Committee, after debate and a vote in executive session, were to authorize the dissemination of Trump's tax return into the public record of the House," University of Southern California law professor Edward Kleinbard writes in the Los Angeles Times. Unlike the president, who still has the right to view any taxpayer's returns, "tax law expressly permits" the Ways and Means Committee to publicly release such returns, with proper justification. "Does the Ways and Means Committee have a solid reason to put Trump's tax returns in the public House record?" Kleinbard asks. If we get to that point, "it turns out that the Republicans have poisoned their own well."

So "if Trump challenges a public release of his tax information in court," Kleinbard says, "he should fear that Republicans' 2014 political power move could color the outcome."