The lights of the state Capitol glow into the night in Sacramento, Calif., Wednesday, Aug. 31, 2022. (AP Photo/Rich Pedroncelli, File)

Given Donald Trump’s plot to overturn the 2020 presidential election, it’s unsurprising that a recent survey by the National Opinion Research Center found that 52 percent of Americans believe that our democracy is in serious trouble. Their skepticism includes congressional gerrymandering—when the party controlling the state legislature draws the state’s congressional and state legislative districts in ways that give them significant advantages in future elections.

While it may be hard to believe, an exclusive, new statistical analysis shows that state-level reforms, big data, and state court rulings ended gerrymandering’s grip on the partisan makeup of Congress in the last three elections. Less surprisingly, it could come roaring back if Supreme Court radicals have their way.

Following the decennial census, state legislatures redraw their state’s congressional districts. There is a simple test of the impact of partisan gerrymandering nationwide: Are either party’s seats in the House of Representatives substantially larger than its share of the popular vote in those elections? For decades, the answer was usually yes because of gerrymandering.

Following the 1990 census, for example, Democrats controlled redistricting in 29 state legislatures versus six by the GOP. (The rest were divided.) In 1992, Democrats won 54 percent of the two-party national vote in House races. In a world where congressional district lines are drawn without either side having an unfair advantage, that vote should translate into about 235 Democratic seats in the House (54 percent of the 435 members). Instead, gerrymandering helped Democrats win 258 seats.

Similarly, following the 2010 census, GOP state legislatures dominated redistricting in 27 states compared to 15 for the Democrats. In the 2012 House elections, Democrats narrowly outpaced the GOP in the nationwide vote. Nevertheless, Republicans in those elections claimed 234 seats to the Democrats’ 201. That was business as usual for gerrymandering.

Despite our polarized politics, gerrymandering has become less of an issue in the outcome of congressional races. In the last three congressional elections, gerrymandering produced no significant advantage for either party. Following the 2020 census, Republicans controlled 29 state legislatures compared to 19 for the Democrats. Yet gerrymandering had no effect on the results of the recent 2022 midterms: GOP House candidates won 51.4 percent of the national vote while 48.6 percent supported Democrats, and Republicans won 221 seats or 51 percent compared to Democratic victories in 213 races or 49 percent.

The story was the same in the 2020 House elections when the national vote for the House split 51.6 percent for Democrats to 48.4 percent for Republicans—and Democrats won 222 House seats or 51.2 percent compared to Republicans’ 212 seats or 48.8 percent of the seats. Democracy also prevailed in 2018, when Democrats took 54.6 percent of the vote and won 235 seats or 54 percent of House seats compared to Republicans with 45.4 percent of the vote and 199 seats or 45.8 percent of the House.

How did gerrymandering lose its power to skew the party makeup of Congress? Part of the answer is that 10 states have ended gerrymandering by shifting the authority to draw new district lines from state legislators to independent, non-political commissions. Those nonpartisan commissions are now in place in six blue states (California, Colorado, Hawaii, New Jersey, Virginia, and Washington), two red states (Montana and Idaho), and two purple swing states (Arizona and Michigan). Altogether, they account for 110 seats or 28 percent of the House of Representatives.

But the majority parties in the other 40 states continue to approach redistricting as a political opportunity—and in the era of big data, the resources for successful gerrymandering have never been greater. Both parties can access databases with all the information they need to predict voting behavior, including every adult’s age, gender, income, race, education, occupation, party registration, and past voting history, by household. It’s simple to apply that data to geography-based software to draw House districts to one party’s substantial advantage.

Ironically, this use of big data has contributed to the declining effectiveness of gerrymandering nationally because anyone can purchase the data and software. So, the Republicans’ edge in Texas redistricting for the 2022 elections, for example, was essentially offset by the Democrats’ edge in Connecticut. And when one party in a state uses big data analysis to tilt the electoral playing field, the other party and interested outside groups can use the same analysis to challenge their opponents’ plans in court.

The result has been an avalanche of lawsuits over partisan gerrymandering. The 2021/2022 redistricting cycle prompted more than 100 such suits attacking the proposed new district boundaries in 33 states, many of which prevailed. Without the successful lawsuits overturning proposed gerrymanders in North Carolina and Pennsylvania, two states with Republican legislatures, the GOP would have a much larger House majority today regardless of their slim margin in the 2022 popular vote. And without the successful lawsuit against the Democrats’ proposed redistricting plan for New York, the Republican margin in the House today could well be one seat instead of five.

Most of these challenges happen in state courts because the Supreme Court has virtually greenlighted most gerrymandering. In 2019, it ruled that the most egregious partisan gerrymanders are still “political matters” that lie beyond the authority of federal courts. That decision limits challenges to gerrymandering in federal courts to racial gerrymandering cases since, under the Equal Protection Clause and the one person/one vote doctrine, state legislatures have been barred from using race as the dominant factor in redistricting. But the High Court recently questioned that protection, too: Last February, they held that Alabama could use a redistricting plan for the November elections despite rulings by lower federal courts that it was an unlawful racial gerrymander.

That leaves state supreme courts as virtually the only resort to challenge egregious partisan or racial gerrymandering under provisions of their state constitutions, as happened in the recent cases involving North Carolina, Pennsylvania, and New York. But even that route is under attack. The Supreme Court is considering the claim of North Carolina legislators that state courts lack the authority to consider any redistricting case.

Their argument rests on a far-right theory that holds that state legislatures are the sole authority for determining how federal elections are conducted in their states, regardless of their state constitutions. Based on oral arguments heard last month, Justices Clarence Thomas, Samuel Alito, and Neil Gorsuch seemed inclined to agree, and Justice Brett Kavanaugh appeared to be on the fence.

The Court is expected to rule on the case by the end of its term this summer. If Alito, Thomas, and Gorsuch can muster a majority for their view, it will greenlight a new era of unfettered gerrymandering. It also could give state legislatures the authority to ignore the popular vote for any federal office and select the winning candidate themselves—a ploy advanced by John Eastman to overturn Trump’s 2020 defeat. Such a ruling would not only supercharge partisan gerrymandering, but it could end American democracy as we’ve come to know it.

Robert J. Shapiro

Follow Robert on Twitter @robshapiro. Robert J. Shapiro, a Washington Monthly contributing writer, is the chairman of Sonecon and a Senior Fellow at the McDonough School of Business at Georgetown University. He previously served as Under Secretary of Commerce for Economic Affairs under Bill Clinton and advised senior members of the Obama administration on economic policy.