Partisan redistricting gave Republicans control of the House. Will a conservative Supreme Court take that advantage back?

In the upcoming Moore v. Harper case, the Supreme Court will effectively be deciding between empowering state legislatures in state elections and protecting the gerrymandering advantage that delivered the narrow 2023 GOP House majority. It cannot do both.

Although the votes are not final, it seems likely Project REDMAP, a well-funded effort launched in 2010 to win state legislatures so Republicans could aggressively gerrymander districts, will deliver the clear partisan win it was designed for. The 2022 Florida gerrymander alone appears to have delivered the House majority — not to mention aggressive GOP gerrymanders in red states such as Alabama, Louisiana, Ohio, Texas and others.

Democrats’ willingness to “play by the rules” has further tilted the House election field towards the GOP. Many blue and purple states have adopted nonpartisan redistricting. Even when Democratic state legislatures have tried to pass hardcore gerrymanders, they have often been blocked by Democratic-appointed state courts. This happened in Maryland and New York, where accepting court changes cost the Democrats at least three House seats.

By contrast, in Ohio the Republican legislature ignored court order after court order until it was too late. This meant gerrymandered lines that violated the Ohio constitution were used for this election.

But the GOP House advantage in gerrymandering will largely disappear if the Supreme Court approves the independent state legislature theory at the heart of Moore v Harper. When North Carolina state courts ruled that the legislature’s partisan gerrymander was a violation of the state constitution, the state legislature sued in federal court, arguing that state legislature powers under Article I Section 4 are not bound by state laws or even state constitutions — and thus that state courts have no power to block state legislatures from extreme partisan gerrymandering.

Most attention on Moore v. Harper has focused on the danger that it would allow state legislatures to decide which candidate gets the state’s electoral votes, regardless of the popular vote in the state.

But Moore v. Harper is at its core a redistricting case. If the Supreme Court decides state courts and constitutions can never overrule state legislatures regarding federal elections, that freedom cannot be limited to just red states.

That egregious New York Democratic gerrymander? It would go into effect — state courts could no longer block it. The California state legislature would similarly not be bound by the voter-passed propositions that require nonpartisan redistricting and would have every incentive to hammer a partisan gerrymander in a state with 52 House seats.

To be clear, a nationwide competition between red and blue states to screw the other party would be terrible for the nation. As would the prospect of state legislatures nullifying elections and choosing their own presidential electors. We hope the dangerous implications of the independent state legislature theory are understood by all nine justices on the Court.

But here is where cynical partisan self-interest may combine with legal logic and concerns over Supreme Court legitimacy to lead the court to reject Moore v. Harper. Granting state legislatures freedom from state courts and constitutions would also allow blue state gerrymanders — many of which have been blocked until now. Although the spiral of competing partisan gerrymanders would be bad for the country, such a spiral would largely level a playing field on which Republicans have long held an edge.

Ironically, what may keep an increasingly partisan Supreme Court majority from empowering extreme partisan gerrymandering or permitting state legislatures to ignore the voters in presidential elections could well be their own partisan self-interest.

The Court’s justices must decide whether they want to let state courts stop New York’s anti-Republican gerrymander or let state legislatures pick presidential winners. Because they can’t have both.

Jeremy Mayer is an associate professor at the Schar School of Policy and Government at George Mason University. Patrick M. (Mike) Condray is a former member of the federal Senior Executive Service and retired U.S Air Force colonel who is researching ways to preserve and improve democracy in the U.S.