It's no secret that partisan state legislators, once in power, frequently try to alter voting laws to give their party an advantage.
But increasingly, when those laws are challenged in federal court, the outcome appears to turn on whether the judges or justices hearing the case were appointed by Republicans or Democrats.
Last month, North Carolina's Republican leaders were blocked from enforcing several new restrictions on voting that had been adopted over the fierce opposition of Democrats. They included less time for early voting and a requirement that a registered voter show one of several specific types of photo ID cards.
A federal judge appointed by former President George W. Bush had upheld the full law in April, deciding the regulations were reasonable.
They were struck down in late July by a panel of three judges of the 4th Circuit Court of Appeals, all of them Democratic appointees, who said the new rules violate the federal Voting Rights Act because they "target African Americans with almost surgical precision."
They noted the law would allow people to vote by showing a military or veterans ID, but not if they had photo IDs showing they worked for a city or a state agency, were enrolled in a state university or received public assistance. More whites than blacks rely on mail-in ballots, and these were "exempted" from the photo ID rule, the appeals court noted.
When the state's Republican governor appealed to the Supreme Court, he lost when the justices split 4-4. The high court's four Republican appointees voted to restore the GOP-backed rules, while the four Democratic appointees refused.
Three years ago, the high court split 5-4 to weaken part of the Voting Rights Act that had prevented Southern states and counties from making changes in their voting rules without clearing them with the U.S. Justice Department. The court's five Republican appointees voted to strike down this part of the law, while the four Democratic appointees dissented.
Election-law experts and voting-rights advocates say they are dismayed to see the partisan divide over election rules reflected in the courts.
"I wasn't surprised North Carolina's appeal was turned down. They had a very weak argument, but I am surprised it got four votes," said Daniel Tokaji, who teaches election law at the Ohio State University. "I don't think the current Supreme Court can be relied upon to protect the right to vote, even when there is evidence of intentional discrimination like we saw in North Carolina."
UC Irvine Law Professor Richard Hasen points out the partisan judicial divide is hardly a new phenomenon. In the Bush vs. Gore decision in 2000, the court's five most conservative justices, all Republican appointees, voted to halt the ballot recount in Florida, thereby preserving George W. Bush's narrow victory.
But prior to 2010, the court had two liberal-leaning Republican appointees in Justices John Paul Stevens and David Souter. And not all lower courts judges are predictable when confronting new election regulations.
"But partisanship is still a pretty good predictor of how judges will vote in these 'voting wars' cases, and it is not because the judges are consciously trying to help their political parties," Hasen said. "It is that Democrats and Republicans tend to see these issues differently, with Democrats believing these laws present a greater danger of suppressing votes, and Republicans believing these laws are still necessary for anti-fraud purposes or to promote public confidence."
And sometimes, there are exceptions.
Michigan's Republicans lost last week when they tried to end the state's 125-year-long practice of allowing straight-ticket voting. With Donald Trump at the top of ticket, they worried many voters might check the box for a straight Democratic vote and thereby hurt GOP candidates running for local, state or federal offices.
A federal judge appointed by President Obama agreed with civil rights lawyers who said this change could cause confusion and longer lines at polling places, particularly in the Detroit area. He blocked the changes from taking effect, and a three-judge panel, all Democratic appointees, upheld his decision in August.
Michigan's Republican attorney general asked to the Supreme Court to revive the law, but fell short. Justices Clarence Thomas and Samuel A. Alito Jr., both Republican appointees, said they would grant the appeal. The other six justices said nothing, but the outcome suggests Chief Justice John G. Roberts Jr. and Justice Anthony M. Kennedy agreed with liberals to reject the appeal.
In a pending case from Ohio, the court will consider whether the state may cut back on the number of days for early voting.
Ohio adopted early voting after an election-day debacle in 2004 in which some voters waited hours in line to cast a ballot. Since then, African Americans have been more likely than whites to vote in the period before election day.
Ohio wants to eliminate its first week of early voting, a time when voters can re-register and cast at a ballot at the same time. Republicans who sponsored the change say the state would still offer 23 days for early voting, among the most generous in the nation.
Democrats oppose the reductions, saying more than 80,000 voters cast ballots in 2012 during this first week of early voting. They noted, too, that each county offers early voting at only one polling place.
In May, U.S. District Judge Michael Watson, a Bush appointee, agreed with Democrats that the state did not have a good reason for reducing the days for early voting, and he blocked the change.
But in August, the 6th Circuit Court of Appeals, in 2-1 ruling, reversed his decision. Two Republican appointees said judges should not "become entangled, as overseers and micro-managers, in the minutiae of the state election process." The dissenter, a Democrat, said minority voters in Ohio's largest cities took advantage of the opportunity to re-register and vote during one trip to the county election office.
The Ohio Democrats appealed to the Supreme Court last week, urging the justices to restore the full period for early voting.
But it takes a majority of five justices to issue such an order, so the Democrats cannot win without support from at least one of the court's Republican appointees.
"In the Ohio case, I expect that we won't see more than two votes in favor" of the appeal, Hasen said, citing Justices Ruth Bader Ginsburg and Sonia Sotomayor. "So that may show it is not a complete partisan divide."
A decision is expected this week.
On Twitter: DavidGSavage
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