What will happen in the 2020 redistricting cycle if the Supreme Court follows the advice of the defendants in the Maryland and North Carolina cases and holds that partisan gerrymandering claims are nonjusticiable? Some may think that, in that event, the status quo will more or less continue. Parties in full control of state governments will keep cracking and packing the opposing parties’ voters, thereby securing partisan advantages that are significant—but usually not enormous or certain to endure for the rest of the decade. This view, however, is probably mistaken. Thanks to a number of technological and legal developments, we are likely to see unprecedented abuses in the next cycle if the Court guarantees that partisan gerrymanders will not be struck down.

The first of these developments (and the one that has attracted the most attention) is the emergence of redistricting algorithms that can quickly generate many maps based on whatever criteria the user specifies. To date, these algorithms have mostly been used in litigation against alleged partisan gerrymanders. Plaintiffs have shown that challenged plans are much more biased than randomly created maps that ignore partisanship but achieve defendants’ nonpartisan goals. But nothing prevents the algorithms from being deployed for ill rather than for good—to engage in gerrymandering instead of to curb it. The user simply has to instruct the program to consider partisanship, and to produce maps that comply with traditional principles while yielding a large and durable advantage for the user’s preferred party.

Accordingly, if the Court rules for the defendants in the Maryland and North Carolina cases, the next cycle will be the first to feature computer-optimized “stealth” gerrymanders. These maps will appear unremarkable to the naked eye, comprised of reasonably compact districts that split relatively few political subdivisions and communities of interest. Yet the maps will attain their partisan aims even more effectively than the flamboyantly shaped districts of yesteryear, massively and reliably benefiting the line-drawing party in election after election.

The second notable development is the compilation of huge voter databases (by both the major parties and outside vendors like Catalist). Crucially, these databases include an evaluation of each person’s likelihood to vote and probable partisan preference if she does go to the polls. Mapmakers have not yet used this information, relying instead on precinct-level election results to gauge voters’ partisanship. But mapmakers will use this information in the next cycle because it makes possible more fine-grained—and thus more potent—cracking and packing.

Suppose, for example, that a given precinct is divided evenly between the parties. (This is actually quite common; even in this era of the “big sort,” many precincts are competitive.) A 2011 gerrymanderer would have been unable to do much with this precinct, lacking any data about partisan variation within it. A 2021 gerrymanderer, in contrast, will know which individual voters in the precinct (at which geocoded addresses) are Democrats or Republicans, liberals or conservatives, likely or unlikely voters. It will be child’s play for a Democratic line-drawer, say, to submerge some of the precinct’s Republicans in a Democratic district while cramming others into an overwhelmingly Republican district. This kind of sub-precinct precision used to be impossible but is now entirely feasible.

The third development—mid-decade re-redistricting—made a limited appearance in the previous cycle and has barely occurred in the current cycle. In the 2000s, a few states (most notoriously Texas) voluntarily redrew their maps after a party won full control of the state government and decided it wanted a larger electoral edge. In the 2010s, such discretionary revisions have not taken place (at least not plan-wide, though several individual districts have been adjusted). Few parties have gained “trifecta” control after competing in maps designed by other actors. Most maps have also performed as their drafters intended, giving the drafters little incentive to redraw the lines.

In the 2020s, however, mid-decade re-redistricting will likely make a comeback if the courts vacate the field. Numerous states will have to enact new plans under divided government in 2021. In any of these states, if a party manages to win full control of the state government later in the cycle, it will have few qualms about redoing the map and thus boosting its prospects in subsequent elections. Even in states where a party enjoys trifecta control in 2021, it may amend districts as the decade unfolds, adding its voters to seats that are slipping from its grasp and subtracting them from seats that have become secure. Such fine-tuning has been rare in recent years, but it would become the optimal redistricting strategy if there were no chance of a judicial check.

Lastly, there has been a very strong norm of drawing contiguous districts for most of American history. The Court has reinforced this norm by striking down highly irregular districts that, in its view, were designed for primarily racial reasons. But neither federal law nor any Court decision actually requires districts to be contiguous. Some states do mandate contiguity, but many others do not. In twenty-eight states, in fact, congressional districts can include nonadjacent territory—or even be wholly nongeographic—without violating any legal provision.

If any possibility of liability for partisan gerrymandering vanishes, then, we shouldn’t be surprised if a state decides to experiment with noncontiguous districts in the next cycle. Take my home state of Illinois (which does not require congressional districts to be contiguous). Why should Democratic mapmakers bother with the “pizza slice” method: carefully crafting districts that start in heavily Democratic Chicago and then wind their way into the city’s more Republican suburbs and exurbs? It would be so much easier to combine clusters of urban Democrats with somewhat smaller concentrations of downstate Republicans if the two groups didn’t have to be geographically connected.

Noncontiguous districting may sound farfetched. And for the moment at least, it is. But if the Court announces that all partisan gerrymanders are immune from judicial scrutiny, the tactic may soon be our new reality. And so too may all the other stratagems that have not yet been tried, but that are now legally and technologically viable.