The U.S. Supreme Court took a pass on setting limits on extreme partisan gerrymandering on Monday, saying the plaintiffs in the case didn’t have standing to challenge Wisconsin’s entire statewide assembly map.
The decision came in a case called Gill v. Whitford, which advocates had hoped would allow the court to clarify if partisan gerrymandering could be so egregious that it violated the U.S. Constitution. The court has never said partisan gerrymandering is unconstitutional, leaving lawmakers from both political parties free to draw lines to their advantage.
Redistricting is usually done once every 10 years, so an effective gerrymander can have profound political consequences for the rest of the decade. Many believe advances in technology and data analysis will make partisan gerrymandering during the next round of redistricting, in 2021, even more severe.
The case involved a challenge to Wisconsin’s state assembly map. Republicans controlled the redistricting process in Wisconsin and worked in secret to draw a map to cement GOP control over the chamber.
Their plan worked. In 2012, they won 60 of the chamber’s 99 seats, even though then-President Barack Obama had won the state and Republicans only got 47 percent of the vote. The GOP won 57 percent of the assembly vote in 2014 and increased its majority in the assembly to 63 seats. In 2016, the party’s share of the assembly vote dropped to 53 percent, but Republicans picked up an additional seat in the assembly.
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Wisconsin Republicans weren’t alone in gerrymandering. During the 2010 midterm elections, Republicans targeted state races in which they had a chance to flip control of state chambers and control the redistricting process. That effort succeeded and Republicans ruthlessly gerrymandered seats to their advantage. In North Carolina, the Republican lawmakers overseeing the redistricting process talked openly about how much of an advantage their map would give Republicans. Challenges to the North Carolina congressional map, as well as the Maryland map, which is gerrymandered to favor Democrats, are also pending before the court.
The challengers in the Wisconsin case, 12 voters in the state, said the state assembly map was a partisan gerrymander that treated Democrats and Republicans differently, thus violating their rights guaranteed by the First and 14th amendments. They said the election results over three federal elections offered clear evidence that Republicans had drawn a map making it nearly impossible to take control of the chamber.
But Wisconsin lawyers said lawmakers hadn’t done anything unconstitutional by drawing maps to their advantage. They noted that the Constitution gives state lawmakers power over redistricting, a sign that the drafters of the document anticipated partisanship to play a role in the process.
They also pointed to a 2004 case called Vieth v. Jubelirer, in which the Supreme Court declined to strike down Pennsylvania’s congressional map as an unconstitutional gerrymander. Four justices in the majority wrote that it was impossible to determine when a partisan gerrymander violated the Constitution. Justice Anthony Kennedy, however, wrote separately, saying that such a standard might exist.
The challengers in Gill took up Kennedy’s invitation. They offered a range of standards they hoped he might like in hopes of earning his vote, which was seen as crucial in winning the case.
Many of those proposed tests relied on mathematical calculations to help the justices assess how firmly a map cemented one party’s power. One of the tests that got much attention in the case was called the “efficiency gap.” It offers a formula for calculating how many votes each party wastes in a given election in an attempt to quantify the severeness of a gerrymander. The party in power is extremely likely to maintain its majority when the efficiency gap is greater than 7 percent, experts say.
During oral argument in October, Chief Justice John Roberts was skeptical of the efficiency gap and other standards, labeling them “sociological gobbledygook.” He worried that getting involved in partisan gerrymandering would worsen the court’s standing in the public’s eye because the average American would think the justices were favoring one party over the other.
The standards the challengers were offering “doesn’t sound like language in the Constitution,” Roberts said.
This article originally appeared on HuffPost.