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The master Republican mapmaker Tom Hofeller is among the visionaries who understood how sophisticated new GIS software and powerful new data sets provided an opportunity for the GOP to gerrymander itself decadelong advantages in the U.S. House of Representatives and state legislatures nationwide. Hofeller trains state legislators and junior line-drawers, however, with a PowerPoint so old-school that it looks like it might have been designed on a Commodore 64. There are no special effects to clutter Hofeller’s most important laws of redistricting: Avoid recklessness. Always be discreet. Avoid email.

In case that message does not sink in, Hofeller repeats and underlines this advice. “Emails are the tools of the devil,” he cautions. “Remember—A journey to legal HELL starts with but a single misstatement OR a stupid email!” “Remember, the court record is already open.” “Remember recent email disasters!!!”

Time and again, Hofeller’s political allies have failed to heed his advice. The most recent example: newly disclosed emails—part of a federal court challenge to the constitutionality of the Michigan map by the League of Women Voters—that reveal just how determined GOP operatives, mapmakers, and congressional staffers were to design maps that would provide Republicans with a full decade of dominance. (Emails and correspondence between Hofeller and Michigan Republicans, who have worked together in the past, have also been requested as part of discovery.) Those who are dejected about the Supreme Court’s refusal to put an end to extreme partisan gerrymandering should take heart. The next verdict on partisan gerrymandering will come this fall from voters in Michigan and three other states where meaningful reform is on the ballot. Even if these damning emails don’t move the high court, they’re almost certain to anger American voters.

Michigan Republicans have long denied that partisanship had anything to do with the congressional districts they drew after the 2010 census, a map that has locked in nine of the state’s 14 congressional seats for the GOP in every election since, even in years when Democrats earn many more statewide votes. They have insisted that Voting Rights Act requirements and the state’s political geography—Democratic voters are clustered in Detroit and Ann Arbor, while Republicans are spread more efficiently throughout the state—baked in its red edge naturally and inevitably.

Behind the scenes, they were making very different claims. “In a glorious way that makes it easier to cram ALL of the Dem garbage in Wayne, Washtenaw, Oakland and Macomb counties into only four districts,” wrote Jack Daly, the chief of staff to then GOP congressman Thaddeus McCotter, in a note to mapmaker Jeff Timmer and longtime strategist Robert LaBrant. Daly asked Timmer to swap neighborhoods in predominantly black Wayne County for suburban voters in West Bloomfield to meet the “obvious objective” of “putting dems in a dem district and reps in a GOP district.”

Another email celebrated a vulgar contour on the map that looked like an extended middle finger, and the likely impact that feature would have on a Democratic incumbent. “Perfect,” a colleague wrote Timmer. “[I]t’s giving the finger to sandy levin. I love it.”

In another email, discovered in trial documents by both the Bridge and the Detroit News, LaBrant told Timmer that national Republicans had suggested a map with 10 Republican seats and just four for the Democrats. That seemed too reckless for LaBrant, who counseled that “we needed for legal and PR purposes a good looking map that did not look like an obvious gerrymander.” LaBrant later observed that “we’ve spent a lot of time providing options to ensure we have a solid 9-5 delegation in 2012 and beyond.”

This push to turn Michigan red was part of a national movement. Savvy GOP strategists at the Republican State Leadership Committee, led by Chris Jankowski and Ed Gillespie, carefully orchestrated the GOP’s 2010 redistricting play, an audacious comeback move after being wiped out in 2008 by Barack Obama and losing control of both chambers of Congress. They named it REDMAP, short for the Redistricting Majority Project. By the time Democrats woke up and realized what the GOP was up to, Republicans had redrawn 193 of the 435 U.S. House districts. The lines, drawn by Hofeller, Timmer, and other GIS geniuses, held back the Democratic surge in 2012. The GOP held the House of Representatives 234–201 that year despite winning 1.4 million fewer votes nationwide.

Trouble is, some mapmakers forgot email was the tool of the devil. While the gerrymanders they crafted have yet to be undone at the ballot box, their partisan braggadocio has offended judges of all ideologies and provided the proof that something more than politics as usual was afoot during the 2010 redistricting cycle.

In Florida, despite the overwhelming passage of two 2010 state constitutional amendments demanding nonpartisan redistricting, GOP legislators ran sham public hearings while operatives drew the real maps in the shadows and funneled them into the public process. They left such a voluminous paper trail of draft maps and talking points that an outraged federal judge demanded that several Republican congressional districts be redrawn. “[T]his group of Republican political consultants did in fact conspire to manipulate and influence the redistricting process,” Judge Terry Lewis ruled in 2014.

Emails from Ohio revealed how GOP operatives charged with redistricting moved the entire process away from the Capitol and into a suite at the Doubletree Hotel that they dubbed “The Bunker.” On their personal Gmail accounts, strategists and politicians shared increasingly partisan indexes and algorithms, made last-minute fixes to aid campaign contributors, pledged fealty to national GOP goals, and shared virtual high-fives when they finished.

These emails strip aside wonkish debates and make it extremely clear that politicians are doing all they can to choose their voters.

These map-makers didn’t run afoul of any laws—partisan gerrymandering is not illegal. Also, the impact of their work hasn’t been a secret. Multiple studies have demonstrated the historic, durable nature of the Republican gerrymanders in Wisconsin and North Carolina. And just last month, the Citizens Research Council of Michigan used several statistical tests to show the tilt embedded into the state’s maps, conclusively dismissing natural clustering or the state’s geography as the cause, and finding that “the Michigan legislature has gone beyond justifiable factors in drawing districts to advantage one political party.”

These sorts of emails, and the very clear intent behind them, also failed to convince the Supreme Court in the Wisconsin or Maryland cases this spring—though, to be clear, they punted those cases back to the lower courts on standing, specifically declined to rule on the merits and clearly expressed outrage and distaste over the obvious partisanship. In Benisek v. Lamone, which challenged Maryland’s Democratic gerrymander, Justice Stephen Breyer beseeched his colleagues to act in part because of the email record, arguing that “we’ll never have such a record again. I mean, the people who do the gerrymandering are not stupid.”

The public isn’t stupid either. These emails strip aside wonkish debates and make it extremely clear that politicians are doing all they can to choose their voters, and to make elections less meaningful and competitive. It shows that redistricting is not a geographic inevitability but rather a series of specific choices, made by committed partisans armed with precise data, wedded to a goal of decadelong domination.

When the Supreme Court dodged the Maryland and Wisconsin cases, the fight for fair maps shifted from the courts to the ballot box. Earlier this year, a petition drive forced Ohio legislators to agree to a new bipartisan process for drawing congressional lines in 2021. This November, redistricting reform will be on the ballot in Colorado, Utah, Missouri, and, yes, Michigan. These emails may not shift the U.S. Supreme Court, but they reveal the kind of political hypocrisy that infuriates Americans of all ideological stripes. We’ll see in November whether voters punish mapmakers who failed to avoid recklessness, weren’t discreet, and didn’t avoid email.