In a major victory for voting rights on Monday, the Supreme Court affirmed a lower court ruling issued last year that had struck down 28 of North Carolina’s 170 state legislative districts on the grounds that Republicans had unconstitutionally used race in drawing these maps in the first place. These lines will now have to be redrawn, and new elections will be held under them, most likely next year or possibly even later this year. When that happens, Democrats could finally break the GOP’s years-long veto-proof supermajorities in the legislature, which Republicans have used to run roughshod over democratic norms and impose a radical conservative agenda on an evenly divided swing state.

So why did the courts determine these lines were invalid? Republicans had taken seats like the 21st State Senate District in Fayetteville—the tentacular monstrosity you see at the top of this post—that had a plurality of African-American voters and made them majority black. Republicans claimed that they were required to do so under the Voting Rights Act so that black voters could elect their candidates of choice, but that argument was entirely pretextual.

That’s because black voters, even in plurality-black districts, were already able to elect their preferred candidates—typically, black Democrats. Republicans merely sought to pack as many black voters into as few seats as possible in order to make surrounding seats whiter. In the South in particular, blacks tend to vote overwhelmingly Democratic while whites vote heavily for Republicans, so reducing the black population in these neighboring seats quite simply made it easier for the GOP to win them.

Unfortunately, there’s one big hitch. Though the courts have ordered new maps, the very same Republicans who benefitted from the gerrymanders that were just struck down will get to draw up those new lines. Whatever new districts they produce, Republicans will now claim that they’re only taking partisanship (and not race) into account. We know this because the exact same thing happened with the state’s congressional map, which was also struck down as an illegal racial gerrymander but reconstituted (so Republicans said) as a purely partisan construct—something the Supreme Court still tolerates.

But the GOP will still face new constraints on how it can use race when it goes back to the literal drawing board, and that could make all the difference. The now-invalidated maps were so brutally effective that Republicans won veto-proof three-fifths majorities every election since they were first put in place following the 2010 census. That even includes last year, when North Carolina elected Democratic Gov. Roy Cooper to office.