Justice Sonia Sotomayor, seen here at a Nov. 17, 2015 event in Richmond, hasn’t spoken publicly about the latest Supreme Court nomination. (Mark Gormus/Richmond Times-Dispatch via AP)

The worry these days on the eight-member Supreme Court is finding five votes on a controversial issue. But so far the justices have been unanimous in staying out of the political upheaval that has engulfed their court.

And they received a stern warning last week from Senate Judiciary Committee Chairman Charles E. Grassley (R-Iowa) to keep it that way.

It seems beyond question that Judge Merrick Garland is respected by the justices and a friend to many; the next step for the bright young lawyers who clerk for him at the U.S. Court of Appeals for the D.C. Circuit is often a coveted move down the street to a spot in someone’s chambers at the marble palace at 1 First St. NE.

[Merrick Garland’s instinct for the middle could put hin in influential spot]

And there is little debate that, as Justice Elena Kagan noted last week, there’s a reason that courts work better with an odd number of judges. Stalemates and tie votes already have become an issue in the wake of Justice Antonin Scalia’s death in February.

But so far, at least, no justice has been willing to publicly comment on Garland’s qualifications for moving from the second most important court in the land to the first, nor to render an opinion about the Republican Senate’s refusal to consider President Obama’s nominee in this election year.

Before Justice Sonia Sotomayor spoke and answered questions at St. John’s College in Santa Fe, N.M., last week, for instance, audience members were told not to ask about either Garland or the nomination process.

Kagan also refused to talk about her old friend at an appearance at New York University Law School. As dean of Harvard Law School, their shared alma mater, Kagan had lauded Garland and ribbed him about making it to the bench before she did.

[Merrick Garland’s record of respectful disagreements]

She had the last laugh, of course, but has demonstrated her regard for Garland by hiring eight of his former clerks since she joined the Supreme Court in 2010.

Justice Stephen G. Breyer has shooed away questions about the nomination process in appearances since Scalia’s death, and Justice Samuel A. Alito Jr. told students at Georgetown Law School that the court has had an even number of justices before and “we will deal with it.”

It is the justices’ natural inclination to try to stay out of the political fray, of course. But it is not unheard of for them to venture an opinion about a nominee. Justice Ruth Bader Ginsburg, for instance, came to Sotomayor’s defense before she was confirmed in 2009.

But University of Chicago law professor David A. Strauss, who interviewed Obama last week as Obama made the case for Garland, said the silence from the justices is not surprising.

“I think their inclination would be to avoid doing anything that takes sides in this political fight,” Strauss said.

That made the unusual preemptive warning from Grassley even more surprising.

He was reacting to remarks that Chief Justice John G. Roberts Jr. made before Scalia’s death about the nomination process.

[Political wars damage Supreme Court’s reputation, Roberts says]

Roberts lamented the public’s growing perception of the court as a political body, and the chief justice said the blame started with the Senate confirmation process.

“When you have a sharply political, divisive hearing process, it increases the danger that whoever comes out of it will be viewed in those terms,” Roberts said in a speech to law students just before Scalia’s death.

“If the Democrats and Republicans have been fighting so furiously about whether you’re going to be confirmed, it’s natural for some member of the public to think, well, you must be identified in a particular way as a result of that process,” he said.

Roberts noted that the last three nominees — Alito, Sotomayor and Kagan, all of whom he called highly qualified — were confirmed on largely party-line votes.

“That suggests to me that the process is being used for something other than ensuring the qualifications of the nominees,” said the 61-year-old chief justice.

Roberts has been silent since Scalia’s death and Garland’s nomination, and in his speech on the Senate floor last week, Grassley warned the chief justice should keep quiet on the subject.

Grassley, 82, and running for what would be his seventh term in the Senate, noted a New York Times column in which a law professor said it would be an important move for Roberts, nominated by President George W. Bush, to call for the Republican Senate to make the court whole.

“That’s a political temptation the chief justice should resist,” Grassley said.

In his criticism, Grassley said, Roberts “has it exactly backwards.”

“The confirmation process doesn’t make the justices appear political,” Grassley said. “The confirmation process has gotten political precisely because the court has drifted from the constitutional text and rendered decisions based instead on policy preferences.”

Oh and by the way, Grassley said: “Many of my constituents believe, with all due respect, that the chief justice is part of the problem.”

[Obamacare threatens John Roberts’ dream of a nonpartisan court]

Grassley didn’t mention which of Roberts’s votes “reflected political considerations, not legal ones,” but apparently he is among the conservatives who feel let down by the chief justice’s votes on the Affordable Care Act.

Obama was partly to blame, too, Grassley said. “Not surprisingly, [the court’s] approval rating has dropped most drastically in recent years following the president’s appointment of Justices Sotomayor and Kagan,” he said.

The confirmation of Sotomayor and Kagan to replace Republican appointees David Souter and John Paul Stevens, respectively, have not changed the balance of power on the court that would accompany Garland’s ascension to Scalia’s seat.

It would make a court where Democratic presidents have installed five liberals, while Republican presidents have named the four who are most conservative.

But the next president is likely to make a mark on the court as well, and Obama warned Republicans to think of the future if they recapture the White House.

“So now the Democrats say, well what’s good for the goose is good for the gander," Obama said, adding, “If different parties control the White House and the Senate during that period of time, you’re not going to get any appointments done — which is a disaster for the courts, generally.”

Obama, of course, is an imperfect messenger. As a senator, he voted against Roberts, who he said was qualified for the court but lacked empathy for the little guy. And he was part of an effort to deny a vote on Alito.

He says now that he regrets that decision.