Terry Pell knows exactly what he will do if the now eight-member U.S. Supreme Court disposes of his challenge to labor union fees with a 4-4 tie vote.

“We will ask for a rehearing,” said Pell, president of the Center for Individual Rights, which represents teachers who object to mandatory fees in the case Friedrichs v. California Teacher Association. “The case is too important to punt away with a tie vote.”

In Friedrichs, a tie would mean that the U.S. Court of Appeals for the Ninth Circuit ruling would stand and Pell’s nonunion clients would lose, at least until the court hears a re-argument or another case testing the same issue comes along.

But those are only two possible scenarios as advocates face the new normal of an institution that could be without a full complement of members for a year or longer.

“There’s not a whole lot of precedent for this,” said Jones Day partner Michael Carvin, who argued the case for the objecting teachers in the Friedrichs case on Jan. 11. Carvin compared the situation to a crossword puzzle “with 16 different possibilities.”

forthcoming law review article confirms the rarity of the situation the court faces now. Of the 164 Supreme Court cases that resulted in 4-4 ties since 1925, only 22 were re-argued—the scenario that applies most to ties caused by vacancies on the court.

"It'll be a new experience," Justice Samuel Alito Jr. said Tuesday at an event at Georgetown University Law Center, according to Politico. "There's nothing in the Constitution that specifies the size of the Supreme Court. There have been times in history where the Supreme Court had an even number of justices."

In Friedrichs as with other cases already argued, the court could order re-argument on its own without issuing a 4-4 decision. By tradition, justices vote privately on a case soon after argument, so they already know what the vote is without Justice Antonin Scalia, who died Feb. 13.

But if the court proceeds and issues a 4-4 ruling in Friedrichs, a majority of justices is needed to approve a motion for rehearing, according to Stephen Shapiro of Mayer Brown, co-author of Supreme Court Practice, the bible for court advocates.

“I don’t know if a bloc of four would try to prevent rehearing in such a situation,” Shapiro said. In the past, he added, “Some rehearing petitions have remained pending for a good deal of time and if the case is an important one, this may well occur again.”

As complex as the future of the Friedrichs case may be, others may be even trickier, Carvin said.

Take the Little Sisters of the Poor Home for the Aged v. Burwell group of cases that challenge the workaround the Obama administration devised for religious nonprofit employers to comply with the contraceptive mandate in the Affordable Care Act. If an eight-member court hears those cases and splits, 4-4, it would leave in place a scramble of lower court rulings that conflict with each other.

The court also has the option of dismissing a pending case as improvidently granted, or yanking a case from the docket before it is argued. The court cancels and reschedules an argument rarely, primarily when the justices suddenly want the parties to brief a new issue that was not addressed before.

But Shapiro doubts that many arguments will be canceled in coming months. “Given its general aversion to delay,” Shapiro said, “the court may well decide to proceed with argument to see if a majority opinion could be mustered.”

Chief Justice John Roberts Jr. had his own experience with re-arguments when he served as deputy U.S. solicitor general in the George H.W. Bush administration.

Roberts argued in Bray v. Alexandria Women’s Health Clinic, a clinic protest case, on Oct. 16, 1991, before an eight-member court—a week before Clarence Thomas joined as the ninth justice. The court set the case for re-argument, presumably because of a 4-4 tie, and Roberts argued again nearly a year later. The court ruled, 5-4, against the clinic as Roberts had urged, with Thomas in the majority.

In 2005, the court also acted on its own initiative to set three cases for re-argument so that Justice Sandra Day O’Connor’s successor could vote. Justice Alito joined the high court in February 2006, and all three cases were ultimately decided by 5-4 votes, with Alito in the majority.

The three cases had been argued first before a nine-member court, because O’Connor delayed her retirement until the new justice took office. The re-argument orders came after Alito joined the court, suggesting that they were close cases or Alito’s vote was different from O’Connor’s.

Alan Morrison, associate dean of George Washington University Law School, urged the court to go slow before rescheduling argument, because of the complete uncertainty about when Scalia’s successor will be confirmed.

“This isn’t like 2005 and 2006 when it was just a matter of time that a replacement for Justice O’Connor would be seated,” Morrison, an expert on court procedure, said. “We could be looking at a vacancy that could push re-arguments into the beginning of the 2017 term.”

Reprinted with permission from the February 23, 2016 edition of Supreme Court Brief © 2016 ALM Properties, Inc. All rights reserved. Further duplication without permission is prohibited.