© Provided by Oath Inc. President Trump and Chief Justice John G. Roberts. (Photo illustration: Yahoo News; photos: AP, Jabin Botsford/Pool via Getty Images, J. Scott Applewhite/AP)

The last time an American president was impeached, the chief justice of the Supreme Court — who presides over the Senate trial portion of an impeachment — drew attention mostly because of the four gold stripes on each sleeve of his black robe.

Chief Justice William Rehnquist, 74 years old at the time, largely kept a low profile in 1999 during the Senate impeachment trial of President Bill Clinton. But the gold stripes — which Rehnquist had added a few years prior under the inspiration of “Iolanthe,” a comic opera written in 1882 by Gilbert and Sullivan — drew attention.

If and when President Trump is impeached by the House in the coming weeks, and the U.S. Senate begins an impeachment trial, current Chief Justice John Roberts will likely seek to attract less attention than his predecessor.

“Under the Constitution he has to be there for it, but I think at every turn he will look for ways to have as small a footprint as possible,” said Adam White, director of the C. Boyden Gray Center for the Study of the Administrative State at the Antonin Scalia Law School at George Mason University.

Roberts did not continue Rehnquist’s legacy of wearing gold stripes when he took the court’s top position in 2005, and as American politics has grown more polarized over the last two decades, Roberts has tried to recede from view rather than become more prominent.

“He is very, very wary of the courts being seen as being brought into a political process,” White said.

Because he is required by Article 1, Section 3 of the Constitution to preside over a Senate impeachment trial, Roberts will be a highly visible participant in a high-stakes political showdown that is shaping up to break down on pure partisan lines, much like the 1999 impeachment.

“Supreme Court arguments are not televised. This will make him exposed to the public in a way he’s probably not used to,” said Daniel Epps, a Washington University in St. Louis law professor.

“It will probably be the highest profile thing he’s done since his confirmation,” Epps added.

Roberts likely will aim to be less participant, however, and more of an umpire, a role he embraced in his confirmation hearings before the Senate. “The role of an umpire and a judge is critical. They make sure everybody plays by the rules. But it is a limited role. Nobody ever went to a ball game to see the umpire,” Roberts said at the time.

“Nobody goes to an impeachment to see the presiding chief justice,” Epps said. “So I think he would really bend over backwards to avoid doing anything that could be perceived as having a partisan motivation.”

Senators are likely to welcome that approach. In 1998, they told a Rehnquist aide in a private meeting before Clinton’s impeachment trial began that they were “not looking for a heavy hand from the rostrum,” according to “The Breach: Inside the Impeachment and Trial of William Jefferson Clinton” by Peter Baker.

Senate lawyers told Rehnquist’s aide, according to Baker’s book, that they thought the chief justice should “rule only on evidentiary and ‘incidental’ questions” and avoid weighing in if Democrats sought to get his ruling on a motion to dismiss the articles of impeachment based on standing, or some other consequential motion.

Roberts is likely to follow that model himself. He has been concerned for some time about a loss of public trust in the Supreme Court’s integrity.

“Since 2010, for the first time in U.S. history, all the conservatives have been appointed by Republicans, and all the liberals have been appointed by Democrats,” David Cole pointed out in the New York Review of Books over the summer.

Roberts has increasingly used his rare public appearances to argue against the view that the Supreme Court is a partisan body.

In October 2018, about 10 days after the brutally contentious confirmation hearings for Justice Brett Kavanaugh, Roberts spoke at the University of Minnesota Law School and talked about “how the judicial branch is — how it must be — very different” from the legislative and executive branches of government.

“Our role is very clear. We are to interpret the Constitution and laws of the United States and ensure that the political branches act within them,” Roberts said, adding that this “obviously requires independence from the political branches.”

“We do not serve one party or one interest, we serve one nation,” Roberts said.

A month later, Roberts took the highly unusual step of actually responding to a statement by Trump, rebuking the president and his rhetoric about federal judges.

Trump complained about a decision over asylum policy by the United States Court of Appeals for the Ninth Circuit, and referred to the judge who issued the ruling as “an Obama judge.”

Roberts issued a statement a day later, the afternoon before Thanksgiving. “We do not have Obama judges or Trump judges, Bush judges or Clinton judges,” Roberts said. “What we have is an extraordinary group of dedicated judges doing their level best to do equal right to those appearing before them.”

Roberts’s comments have already provoked some rumblings on the right about whether the chief justice can be impartial in an impeachment trial.

Republicans and Democrats in the Senate will need to reach an agreement on rules for the impeachment trial, such as how much time each side gets to make its case and whether to call witnesses, and who those witnesses will be.

But in the day-to-day conduct of the trial, the presiding officer is always front and center. If senators have a question, they must submit it in writing to the chief justice and he will read it aloud. He can also rule on motions made by either side.

And if things get unruly, he will be pulled into the maelstrom. Trump is nothing if not unpredictable and drawn to provocation, and it’s impossible to know what curve balls he might throw at the Senate during an impeachment trial.

Some have speculated about Trump’s lawyers calling former Vice President Joe Biden as a witness, since the Democratic presidential candidate and his son Hunter were the targets of Trump’s demands that Ukrainian authorities investigate “corruption.”

Whatever the stunt, many expect Trump to try to turn impeachment proceedings into a circus. And it may be then that Roberts would be forced to have a stronger hand, if only to maintain order.

“Maybe a trial would get explosive and maybe Roberts would have to step in and manage things,” White said.

In such a scenario, with partisan passions boiling over, Roberts would likely anger one side or the other — and quite likely both — with his decisions.

The question of how to avoid such a scenario is likely what preoccupies the chief justice in these days before the storm.

“Somebody,” he said in 2015, “does have to represent the institution to the outside world and to the other political branches.”

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