In his wonderful book on pre-1960 redistricting, Partisan Gerrymandering and the Construction of American Democracy, Erik Engstrom describes the wild mapmaking world of the late 19th century. This was a period, like ours, of close elections and severe partisan polarization. It was also an era in which courts didn’t regulate redistricting at all. With no possibility of judicial pushback, parties abused the line-drawing process in every way they could think of. They cracked and packed the opposing party’s voters. They underpopulated their districts and overpopulated the other side’s. And they re-redistricted whenever it would be helpful. Ohio famously used eight congressional district maps between 1878 and 1892.

After last week’s Supreme Court decision in Rucho v. Common Cause, we find ourselves, again, in an age where anything goes. Thanks to Rucho, there is literally no partisan gerrymander a federal court may strike down—no district plan so politically egregious it may be held to violate the Constitution. So what might today’s mapmakers do now that they’re certain the federal judiciary won’t interfere with their work? Quite a lot, it turns out, including several tactics that, to date, have barely seen the light of day.

And what about progressives who oppose gerrymandering—how should they proceed through the Mad Max landscape the court has foisted upon them? Unilateral blue state disarmament isn’t a good option. A better one is to codify the crafting of congressional districts with the aim of national partisan fairness. That way, blue states could either offset red state gerrymanders elsewhere or, if the national playing field is level, adopt fair maps themselves.

Let’s start with the schemes we’re likely to see now that the federal courts have been relegated to the sidelines. One of them is exploiting the redistricting algorithms that social scientists have recently developed. These algorithms churn out huge numbers of maps based on whichever criteria the user specifies. These criteria can be nonpartisan, prioritizing compactness, respect for town and county boundaries, and so on. But they can also be partisan, producing the largest and most durable possible advantage for the line-drawing party. The algorithms thus make possible a new breed of gerrymander—one that looks reasonable to the naked eye, but in fact is optimized to maximally benefit one side over the other.

There are several techniques that parties could use to gerrymander more aggressively than ever before.

Another strategy will be to imitate the re-redistricting of the 19th-century mapmakers. Say that, in the last election, a party won one district by a tighter margin than it expected, and came close to victory in another district but ultimately fell short. Historically, this party would try to do better next time: to raise more money, recruit stronger candidates, and hope for a more favorable electoral environment. After Rucho, however, the party can skip all that and just redraw the lines. It can bolster its position in the district that was slipping away, and add enough of its voters to flip the district that was trending in its direction. And the party can repeat these steps as often as it likes—even every two years, if necessary to keep its edge in the face of a changing electorate.

A final ploy will be to start creating noncontiguous districts: districts made up of separate, unconnected groups of voters. The contiguity norm that has held until now hurts any party whose voters are distributed inefficiently: for example, by living mostly in urban centers. But in the post-Rucho world, no party has to put up with a geographic disadvantage. It can simply take clusters of its voters in one part of a state (like a city) and pair them with smaller pockets of the other side’s voters in some other region (like the exurbs). If these populations are far from one another and different in their needs and interests—well, that’s a shame, but it’s not illegal.

There are several techniques, then, that parties could use to gerrymander more aggressively than ever before. Should they do so? Of course not. Even the Rucho majority agreed that gerrymandering is “incompatible with democratic principles.” Parties shouldn’t do things that undermine core democratic values.

But will they do so? Unfortunately, yes. Before Rucho’s ink was even dry, Republican activists, in particular, were racing to congratulate the court on its decision and to make clear their intent to keep gerrymandering. For instance, former Wisconsin Gov. Scott Walker, now the national finance chairman of the National Republican Redistricting Trust, tweeted about the “big victory in the U.S. Supreme Court,” which will allow “elected officials” to continue to “draw the lines.” Similarly, David Lewis, the architect of the North Carolina map challenged in Rucho, declared “complete vindication” and added that “redistricting is an issue that should be worked on by elected legislators.”

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This poses quite a conundrum for progressives, most of whom now object to gerrymandering and want independent commissions, not politicians, to draw district lines. If blue states follow Walker and Lewis’ lead, extracting every ounce of partisan advantage from their maps, then they’ll be trapped in a race to an undemocratic bottom. On the other hand, if blue states keep transferring mapmaking authority to commissions (as California and New York recently have), then they’ll be unilaterally disarming. Then, blue states will have fair maps and red states will have gerrymanders, giving Republicans a national edge that could entrench minority rule in the House of Representatives.

One solution to this puzzle is for blue states to adopt commissions only if similarly sized red states agree to do the same. The Maryland Senate actually passed a bill along these lines, committing to an independent redistricting process as soon as New Jersey, New York, North Carolina, Pennsylvania, and Virginia make equivalent promises. This bill didn’t become law, though, and the status of interstate pacts is constitutionally murky.

Another option is for blue states to take a no-holds-barred approach to their congressional plans—exploiting redistricting algorithms, re-redistricting frequently, and freely crafting noncontiguous districts—while enacting fair state legislative maps. Why this distinction? Because a state’s congressional delegation is part of the larger U.S. House, while state legislatures are discrete bodies that stand on their own bottom. This means there’s no unilateral disarmament issue with respect to state legislative maps. Whether these maps are skewed or neutral in a given state, the national balance of power is unaffected.

The best idea, though, is for blue states to design their congressional plans using a criterion of countrywide fairness. If the whole U.S. House was biased in a Republican direction, the states would thus manipulate district lines in favor of Democrats. But if the House was balanced or tilted toward Democrats, the states would pass neutral or even pro-Republican maps. This approach would prevent Democrats from being played for suckers in the post-Rucho world. But it would also allow progressives to stay true to their principles: to gerrymander only to make elections fairer overall, and to stop gerrymandering as soon as the national playing field is level.

Update, July 3, 2019: The byline of this piece has been updated with the co-author Aaron Goldzimer.