Under these circumstances, the House has to keep fighting, including by suing civilly to enforce its committees’ subpoenas. During the period that I served in the Office of General Counsel, only two House-subpoena cases ended up in court: Committee on the Judiciary v. Miers (during George W. Bush’s presidency) and Committee on Oversight and Government Reform v. Holder (during Barack Obama’s presidency). I worked on both. These cases provide some guidance on how the current suits will likely unfold, at least at the lower-court level.

In 2007, when Nancy Pelosi was speaker, the House Judiciary Committee subpoenaed former White House Counsel Harriet Miers to testify about, and White House Chief of Staff Joshua Bolten to produce records relating to, the White House’s firing of an unusual number of U.S. attorneys. The Bush White House directed Miers not to appear and Bolten not to provide records, claiming that senior White House aides were absolutely immune from congressional subpoenas (the same claim the Trump White House now makes with respect to McGahn). Ultimately, the committee, after being so authorized by the full House, sued to compel compliance.

U.S. District Judge John Bates, a Bush appointee, ruled in 2008 in the Miers case that senior White House aides are not immune from congressional subpoenas, that Miers had to appear before the committee but could raise privilege objections in response to specific questions, and that Bolten had to either produce the documents subpoenaed or provide to the committee a log of the documents as to which he claimed privilege. Bates also indicated that if further disputes ensued regarding specific privilege objections, he would help resolve them. Miers and Bolten appealed. But shortly thereafter, President Obama was sworn in, and the parties settled: The Judiciary Committee took Miers’s testimony and Bolten produced some, although not all, of the subpoenaed documents.

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In 2011, when John Boehner was speaker, the House Committee on Oversight and Government Reform subpoenaed Attorney General Eric Holder for documents that concerned “Fast and Furious,” an undercover Justice Department law-enforcement operation that went awry and resulted in the death of a U.S. Border Patrol agent. After months of back-and-forth and the production of a small number of documents to the committee, Holder claimed that the remaining documents were protected by a common-law privilege little understood outside legal circles, known as the deliberative-process privilege. As before, the committee, after being so authorized by the full House, sued, this time to compel compliance with certain specific aspects of its document subpoena.

In 2013, U.S. District Judge Amy Jackson, an Obama appointee, ruled that the House had standing to sue. On the merits, however, the case dragged on for several more years—because of the volume of documents at issue, because Jackson allowed the Justice Department to assert new privileges as the case proceeded, and because she concluded that the deliberative-process privilege had some constitutional roots. Ultimately, the committee obtained many, although not all, of the documents it had sought.