In a stirring display of party unity, Republicans across the political spectrum have united to defend Donald Trump’s right to keep his tax returns private. “I’d like the president to follow through and show his tax returns,” Senator Mitt Romney said during a Sunday appearance on Meet the Press, as a preamble to an explanation for why he wouldn’t be joining Democratic efforts to see them. “Going after his tax returns through a legislative action is moronic,” he explained. “That’s not going to happen.” Chuck Grassley, a more vociferous defender of the president, was less wishy-washy. “I don’t want to see them,” he told Fox & Friends Monday morning. “I am not going to request them.”

The problem, Republicans insist, is that while federal tax law allows Congressional committee chairs to request individual tax returns, they need a legitimate legislative reason to do so—and for some, fishing for potential crimes doesn’t make the cut. “It would be a gross abuse of power for the majority party to use tax returns as a weapon to attack, harass, and intimidate their political opponents,” Trump attorney William Consovoy wrote to the Treasury Department on Friday, calling on the I.R.S. to reject a House Democratic request for six years of Trump’s personal and business returns. “Requests for tax returns and return information must have a legitimate legislative purpose. All legislative investigations ‘must be related to, and in furtherance of, a legitimate task of the Congress,’” Consovoy argues, citing Supreme Court precedent. “The Constitution does not grant Congress a standalone ‘investigation’ power; Congress can conduct investigations only to further some other legislative power enumerated in the Constitution.”

Of course, that’s not entirely true. One of the most significant powers entrusted to Congress is the ability to initiate impeachment proceedings—a legitimate legislative process that would surely give Democrats wide latitude to look at Trump’s tax returns, if they have reason to believe that he has committed crimes or otherwise violated his oath of office. But Republicans also know that most Democratic lawmakers don’t want to go there. Impeachment is something that Speaker Nancy Pelosi herself virtually ruled out weeks ago, telling The Washington Post that without “something so compelling and overwhelming and bipartisan” to warrant it, launching impeachment proceedings would needlessly divide the country and make the Democrats look politically motivated. Certainly she wouldn’t pull that emergency lever just to get the upper hand in a potential legal battle over the president’s taxes. Would she?

Congressional Democrats presumably believe they can win the inevitable legal fight regardless. As the conservative political commentator Allahpundit notes: