WASHINGTON — “Has there ever been,” the judge asked, “an instance of such broad-scale defiance of a congressional request for information in the history of the Republic?”
It was the first Friday of the new year, and an appeals court was considering whether President Trump could order his advisers to refuse to comply with congressional subpoenas. The case concerned Donald F. McGahn II, the former White House counsel, but the questions from the judge, Thomas B. Griffith, made plain that the court was struggling with something more general and fundamental.
Judge Griffith was appointed to the court by President George W. Bush and is an authority on the separation of powers, having served as legal counsel for the Senate, including during the impeachment trial of President Bill Clinton. He wanted to know if there was any precedent for a wholesale presidential order to stonewall Congress.
“Has that ever happened before?” Judge Griffith asked.
The administration’s lawyer, Hashim M. Mooppan, gave an answer that underscored the significance of the case. “Not to my knowledge,” he said.
It can be hard to keep track of the lawsuits seeking information from Mr. Trump, his associates, his accountants and his bankers. Three of them are already before the Supreme Court.
But the case heard this month by a three-judge panel of the appeals court, the United States Court of Appeals for the District of Columbia Circuit, is easily the most important.
The Supreme Court cases concern requests for information from private firms. The McGahn case is a constitutional standoff between two branches of government and presents a question that, perhaps surprisingly, has never been definitively resolved by the Supreme Court: May Congress sue the executive branch, whether to enforce a subpoena or for anything else?
In 2015, the Supreme Court left open, as Justice Ruth Bader Ginsburg put it, “the question whether Congress has standing to bring a suit against the president.” She noted that “a suit between Congress and the president would raise separation-of-powers concerns.”
In November, Judge Ketanji Brown Jackson, of the Federal District Court in Washington, ordered Mr. McGahn to testify about what House Democrats said was a pattern of presidential obstruction of justice. She said federal courts may resolve clashes between the other branches and rejected the administration’s argument that close advisers of the president have “absolute immunity” from congressional subpoenas.
The appeals court, acting in the shadow of Mr. Trump’s impeachment, has put the case on a fast track. After it rules, a Supreme Court appeal seems close to inevitable. The case may not be resolved in time to matter in the impeachment trial, but it may nonetheless yield a foundational ruling on the structure of the Constitution.
In its appeals court brief, the administration said the issues in the case were both momentous and novel. “For only the second time in our nation’s history,” the administration told the appeals court, “a court has ordered a close presidential adviser to appear and testify before Congress.” (The first decision, from a trial judge in 2008, concerned a subpoena to Harriet Miers, Mr. Bush’s former White House counsel. The two sides settled before the appeals court could rule.)
At the argument in the McGahn case, Mr. Mooppan, the administration’s lawyer, made two basic arguments, both sweeping. Mr. Trump and his close advisers, Mr. Mooppan said, have absolute immunity from congressional subpoenas, meaning they cannot be made to appear to be questioned about anything at all, whether or not executive privilege or some other protection might apply to particular inquiries.
But Mr. Mooppan said there was no need for the appeals court to decide that issue, as federal courts have no role in adjudicating disputes between the other branches. In 1997, he noted, the Supreme Court rejected a suit against executive branch officials from six individual lawmakers, saying they had not suffered the sort of direct injury that gave them standing to sue.
The D.C. Circuit, however, has said that “the mere fact that there is a conflict between the legislative and executive branches over a congressional subpoena does not preclude judicial resolution of the conflict.” It drew support from United States v. Nixon, the 1974 Supreme Court decision requiring President Richard M. Nixon to turn over tapes of conversations with aides, calling that “an analogous conflict between the executive and judicial branches.”
But the Nixon case arose in the context of a criminal trial, and the Supreme Court went out of its way to say that it was not “concerned here with the balance between the president’s generalized interest in confidentiality” and “congressional demands for information.”
Congress may have ways other than lawsuits to persuade or force the administration to comply, Judge Griffith said at the appeals court argument.
“Congress has plenty of remedies,” he said, including cutting off money or refusing to confirm nominees. “Appropriations power. Confirmation power. Impeachment power. There are lots of remedies that have been used for a long time. What’s wrong with those?”
Megan Barbero, a lawyer for the House, said those methods would not lead to getting the requested information in a timely fashion.
Should the appeals court decide that it has a role to play in the McGahn case, it will have to decide whether Mr. Trump’s close aides have “absolute immunity” from congressional subpoenas. The theory has been pressed by administrations of both parties.
An early articulation came in 1971 from William H. Rehnquist, then a Justice Department official and later the chief justice. He acknowledged that his views were “tentative and sketchy,” but he reasoned that it could not hurt the president to take a hard line.
“In a strictly tactical sense, the executive branch has a head start in any controversy with the legislative branch, since the legislative branch wants something the executive branch has,” Mr. Rehnquist wrote. “All the executive has to do is maintain the status quo and he prevails.”