Opinion | Don’t Be Fooled, Trump Is a Winner in the Supreme Court Tax Case

Sure, the other chamber might try to strip this rider, or the president might threaten a veto of the entire bill containing the rider. But if the chamber seeking the information held firm, ultimately the other institutions would be faced with the choice of either no appropriations bill at all (thus defunding a vast swath of the government) or an appropriations bill with the rider.

Would the chamber stand firm? That would depend on how this fight played out with the public. But in the context of an unpopular president seeking to thwart all congressional oversight, and in the context of a congressional chamber making a targeted use of the power of the purse (going after the White House Counsel’s Office and not, say, the Department of Veterans Affairs), it would stand a good shot at winning the public fight.

But there’s another way, perhaps even less fraught, that Congress can use its power of the purse to enforce information demands if it does some planning. When creating programs in the first place, it can write in requirements that the administration cooperate with congressional oversight in specific ways (as it did, for instance, with the programs created by the CARES Act to respond to the economic disruption caused by the coronavirus).

The president might insist that those requirements are unconstitutional (as Mr. Trump did with the CARES Act). But going forward, as Senator Richard Blumenthal and others have proposed, Congress can write in what lawyers call “non-severability clauses”: essentially, provisions saying that the oversight requirements and the funding itself cannot be separated. If the White House (or the courts) wants to take the position that the oversight is unconstitutional, it’ll have to sacrifice the underlying funds to do so.

The power of the purse is not Congress’s only tool. Under certain extreme circumstances, it can use its own sergeants to arrest those who defy its subpoenas. And depending on the outcome of the November election, Congress may also have the opportunity to pass legislation that would strengthen the role of inspectors general and others who might aid it in its oversight role.

But today’s wins for President Trump and Chief Justice Roberts should make one thing very clear: Whatever mechanisms Congress does choose to buttress its crucial oversight role, it certainly cannot count on the courts to help out.

Josh Chafetz (@joshchafetz), a professor of law at Georgetown University Law Center, is the author, most recently, of “Congress’s Constitution.”