(NewsNation) — The Supreme Court ruled that state courts do have the power to review legislative maps passed by state legislatures in Moore v. Harper, a ruling that is critical for the future of elections.

In deciding the case in favor of North Carolina voters, the Court shot down a legal theory that would have given state legislatures the ability to create partisan voting maps with no recourse for voters.

The Case

In 2021, North Carolina’s Republican-dominated state legislature redrew voting maps based on new population data from the 2020 census. The result was a gerrymandered map that would cement the party’s supermajority in a state that is split close to 50/50 when it come to party affiliation.

Gerrymandering isn’t uncommon when it comes to redistricting, but the map was an extreme example, according to nonpartisan law and policy institute The Brennan Center, as it was more favorable to Republicans than 99.99% of all possible maps.

The Supreme Court previously ruled federal courts can’t hear cases regarding gerrymandering, so voters took their case to the state Supreme Court instead. It struck down the map and ordered a new map drawn by independent experts.

Republican legislatures appealed to the Supreme Court, arguing that state courts don’t have the authority to review election maps. In 2022, after Republicans gained control the North Carolina Supreme Court, justices reversed the earlier decision and said the original map could stand.

When the North Carolina Supreme Court reversed its earlier decision, the appeal was already being heard by the Supreme Court.

The Legal Issue

Republicans in North Carolina argued in favor of the “independent state legislature” theory. It’s based on the Federal Elections Clause, which begins: “The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature..”

Based on that clause, Republicans argued that state legislatures are the sole authority when it comes to elections and state courts have no power of judicial review.

The Decision

The Supreme Court struck down the independent state legislature theory, giving state courts the power of judicial review over election maps and upholding the decision from the North Carolina Supreme Court.

Chief Justice John Roberts wrote the majority opinion in the case, with a concurrence from Justice Brett Kavanaugh. The Court ruled that state courts do have the power of judicial review when it comes to redistricting, but that power is not unlimited and state courts can’t interpret state law in a way that attempts to evade federal laws and protections.

“Although we conclude that the Elections Clause does not
exempt state legislatures from the ordinary constraints imposed by state law, state courts do not have free rein,” Roberts wrote.

Justices Clarence Thomas and Neil Gorsuch dissented, joined in part by Justice Samuel Alito. They wrote that since the North Carolina Court already reversed its ruling, the case was moot and the Supreme Court had no authority.

The Impact

For North Carolina voters, the decision makes little difference. Because the state Supreme Court already reversed its own decision, Republican efforts to redraw maps without outside input will continue.

Nationally, however, the decision blocks a broad GOP effort to create partisan maps and overhaul election laws in their favor.

By striking down the independent state legislature theory, the Court maintained the ability of voters to challenge partisan maps in state courts. Had it decided the other way, majority parties would have had the unchecked ability to create maps in their favor in an effort to maintain their control and circumvent the will of voters.