They also pose a test for a legal premise the court has increasingly cited in recent years as a justification for wading into some preelection showdowns while standing aside in others.

The Purcell principle, named for a dispute over an Arizona voter identification law taken to the court on an emergency basis in 2006, dictates that federal judges should generally refrain from causing confusion by changing voting rules in the lead-up to an election.

While the notion sounds simple enough, its application in practice can often be baffling. And just how to apply the idea of keeping election procedures stable in the midst of an extraordinary national health emergency like the coronavirus pandemic is far from clear.

“It’s being brought up in just about every case right now as we are getting closer to the election,” said Rick Hasen, a University of California at Irvine law professor who coined the term “Purcell principle” in a 2016 law review article. “But it’s not a hard-and-fast-rule, and it’s not well developed.”

The current, short-handed court appeared to hew to the Purcell principle in its Monday order restoring the South Carolina requirement that absentee voters find a witness to sign their ballot materials, although precisely why the court acted remained somewhat murky because only one member — Justice Brett Kavanaugh — explained his rationale.

However, several factors suggested that Roberts and Kavanaugh are voting together in a moderately conservative bloc that is committed to the basic Purcell notion while trying to avoid some of the whiplash from lower-court orders being abruptly reversed by the Supreme Court.

Kavanaugh’s brief explanation, the court’s decision to allow completed ballots received by Wednesday to be counted without a witness signature, and a statement from the court that Justices Clarence Thomas, Samuel Alito and Neil Gorsuch would have voided noncompliant ballots already cast suggested that Kavanaugh and Roberts are viewing Purcell somewhat more flexibly than their other Republican-appointed colleagues.

However, the scope of the concession for cast ballots seems modest, since mailed ballots were only supposed to go out starting this past weekend. In-person absentee voting began in the state on Monday. More than 150,000 absentee ballots have already been requested, with almost 20,000 cast on the first day, The Associated Press reported.

The Supreme Court’s action on Monday effectively nullified an en banc decision of the Richmond, Va.-based 4th Circuit issued Sept. 25 allowing South Carolina absentee voters to cast their ballots without finding a witness to sign the envelope. Opponents of the requirement say it could expose voters and witnesses to unnecessary risk of contracting coronavirus, while supporters say the rule helps protect against fraud.

Kavanaugh’s solo statement in the South Carolina case explicitly cited Purcell, declaring: “This Court has repeatedly emphasized that federal courts ordinarily should not alter state election rules in the period close to an election.”

The jockeying over the principle is evident in another fight the justices are wrestling with right now — a Pennsylvania Supreme Court ruling last month that made some changes to the state’s usual voting procedures, including allowing absentee ballots postmarked by Election Day or lacking a postmark to be counted even if they don’t arrive until three days later.

Republicans have fought the changes by arguing that the state court usurped a role that the U.S. Constitution says can be played only by the state Legislature and that the Constitution also forbids allowing the receipt of ballots after Election Day. But GOP leaders of the Pennsylvania Senate have also cited the Purcell principle as a reason to reject the changes the state’s highest court ordered last month.

“Changing the rules in the middle of the game by informing voters that they now have until November 6 for their ballot to be received risks confusion and the potential for fraud,” Republican election lawyer Jason Torchinsky wrote in a brief filed last week for the state lawmakers.

Lawyers for Pennsylvania Secretary of State Kathy Boockvar, a Democrat, seem to embrace the Purcell principle even more aggressively. In a brief filed Monday afternoon, they devoted four pages to arguing that the notion is as much about federalism as it is about timing. The idea behind the concept, they say, is fundamentally that federal courts shouldn’t be monkeying at the last minute with state-run elections, not that states lack the power to manage that process.

“Applicants’ request for this court’s intervention now is precisely the eleventh-hour federal meddling that the Purcell principle counsels against,” Pennsylvania Attorney General Josh Shapiro wrote. “The senators appear to argue that this court should issue an order preventing those state courts from addressing Covid-19 related emergencies in their respective states. This is directly contrary to the Purcell principle.”

Legal experts say the Supreme Court could broaden the Purcell idea to cover last-minute state court orders, but it’s still unclear whether it would apply to changes sought or agreed to by the election authorities themselves. Also uncertain is whether a state court ruling issued six weeks before Election Day qualifies as the kind of disruptive, late-breaking order the judges in the Purcell case worried about.

“What is the cutoff time? How flexible is it? I think we don’t know what,” Hasen said.

One option for the justices in the Pennsylvania case might be to ditch it on standing grounds, noted Loyola Law School professor Justin Levitt, by concluding that legislative leaders or Republican Party officials simply lack authority to litigate on behalf of the state or lack a concrete injury from the state’s plan to keep counting ballots after Election Day.

A decision a federal appeals court issued last week on a similar dispute in Wisconsin could prove instructive if the justices decide to punt on Pennsylvania.

A three-judge panel of the Chicago-based 7th Circuit held that the Wisconsin Legislature, the Wisconsin GOP and the Republican National Committee lacked standing to ask for changes to an injunction a federal judge issued extending the ballot receipt deadline for six days. The appeals court panel consisted entirely of Republican-appointed judges, including a noted conservative, Reagan appointee Frank Easterbrook.

The panel later agreed to refer the Legislature’s standing to the Wisconsin Supreme Court for another look, but Levitt thinks the approach the 7th Circuit took could prove attractive to some members of the U.S. Supreme Court. “If this court stands for anything, it’s for limiting the applicants who can come into court,” the professor said.

Hasen said he would not be surprised if the Supreme Court acts in that case or another in order to lay down some clearer guidelines about how it is approaching these issues in the pandemic. “That’s one of the reasons we might get something more definitive in these early cases,” he said.

All eyes on Roberts

Predicting what the court will do with the pending and expected future election-related applications involves assessing precedent and legal principles, but it is also prompting a degree of psychoanalysis of the justices — most particularly, Roberts.

Roberts is seen as the most likely justice to break with the court’s conservative wing and deny it the majority it would need to carry the day on the election law cases — at least until a new justice is confirmed. And, as chief justice, he wields some influence over his colleagues and the court’s actions, particularly in terms of the pacing of decisions and the content of opinions he joins.

For Roberts, two competing impulses might be in play: his generally conservative views on election-related legal issues and his stated desire to fight perceptions of the court as a political actor. In a highly polarized time, accomplishing both goals at once might be next to impossible.

“My sense is in this arena, the chief is not really interested in Democratic political success or Republican political or campaign success. His goal is to make sure that the election is not a giant clusterf*** that is laid at his feet,” Levitt said. “I think his primary objective is to stay the hell out of this nonsense.”

Just how likely Roberts is to break ranks with his conservative colleagues on the election-related fights is a matter of considerable debate in legal circles. He has almost never strayed from conservative orthodoxy in cases like redistricting and voting rights. In fact, he’s known as the architect of Shelby County, the court’s 2013, 5-4 ruling that knocked out a central pillar of the Voting Rights Act, outraging civil rights groups.

However, Roberts’ vote in emergency applications related to elections is somewhat less predictable.

In August, the chief justice appeared to side with the four liberals then on the court and Kavanaugh in refusing a Republican Party request to block a plan in Rhode Island to keep waiving certain security measures for absentee ballots due to the pandemic. The high court said the fact that state officials consented to the changes counseled against blocking them.

Since the court doesn’t release vote tallies on such matters, it can’t be said for certain how the chief justice or Kavanaugh voted, but at least one of them joined the liberals in the ruling. Neither man joined the three other GOP-appointed justices in publicly dissenting from the court’s stance.

A similar scenario played out in 2014, when Roberts appeared to join with the court’s liberals and Kennedy as the court blocked a GOP-backed voter ID law from taking effect in Wisconsin shortly before the midterm general election. Again, the court’s three other Republican-appointed justices dissented. And, again, Roberts kept mum.

But earlier this year, Roberts joined with conservatives in a 5-4 decision that blocked a federal judge’s order extending the ballot receipt deadline for the Democratic presidential primary and a state election in the Badger State.

Ginsburg bitterly decried that decision as indifferent to the dangers of the pandemic. She died from other causes last month.

Experts said the South Carolina ruling Monday night was not surprising given how the case unfolded.

“The case seemed an especially strong one for application of the Purcell doctrine,” said Ned Foley, a law professor at Ohio State University.

One aspect of the outcome that did draw attention was that none of the three remaining Democratic-appointed justices noted any dissent — passing up, for now, the chance to act as they did through Ginsburg six months ago in the Wisconsin case and issue a sharply worded disagreement with their Republican-appointed colleagues. One possibility is that the court’s liberals see bigger fights ahead, including in the Pennsylvania dispute, which could be resolved within the next day or so.

Legal analysts say that case has the potential for a more sweeping impact by serving as a vehicle for the justices to grapple with the issue of when state courts can adjust or interpret state laws without usurping a role the Constitution seems to assign to state legislatures. Foley noted that Democrats in Pennsylvania are actually escalating the dispute by trying to get the court to issue a definitive-but-quick decision in the case rather than resolving it with a less-precedent-setting emergency order.

“That seems to elevate the stakes considerably,” Foley said via email.

Kavanaugh’s opinion in the South Carolina case was written in such a way that it leaves his options open for the Pennsylvania fight. He described Purcell as applying to “federal courts,” leaving unanswered the question of whether it should be wielded against a state court decision. But he also emphasized that “a State legislature’s decision” on pandemic related changes shouldn’t be second-guessed, suggesting that a state court’s rulings on the topic might be more vulnerable to challenge.

Although Roberts didn’t sign on to Kavanaugh’s statement, the court’s newest justice quoted Roberts’ ruling with liberals in one of the pandemic-related lockdown cases, emphasizing the primacy of state elected officials in addressing such crises. Since Kavanaugh dissented from that ruling, it appeared he was encouraging the court to adhere to precedent on that issue in upcoming decisions.

Ginsburg’s absence has created a shorthanded court, meaning there’s a greater chance in pending cases and emergency applications of a tie vote, at least in theory.

Even if Roberts or another conservative justice left the fold or was inclined to, a 4-4 result in an election case wouldn’t automatically rule in or out a win for Republican forces. In a tie, the lower court ruling remains undisturbed. That would reject the GOP challenges and hand a victory to Democrats by leaving the Pennsylvania Supreme Court’s ruling in place in that case.

The effect of a tie in other emergency applications the court could receive in the coming days is less clear, but Republicans could wind up with the upper hand in cases coming out of conservative-leaning appeals courts.

Many legal experts believe such ties are a remote possibility because of Roberts’ tendency to side with his conservative colleagues on most matters and his desire to avoid the kind of paralysis a 4-4, preelection vote might signal to the country.

“There are still five conservatives on that court the last time I checked,” Hasen said.