Washington (AFP) – The US Supreme Court hears a case on Wednesday that could fundamentally alter the way democracy operates in America by expanding the power of state legislatures over elections for the White House and Congress.

The case, Moore v. Harper, would potentially give lawmakers in each of the 50 US states more authority in deciding who votes, where and how in federal elections.

The prospect has raised concerns on the left in a bitterly divided country still reeling from Donald Trump's refusal to accept the 2020 election results.

But it has also alarmed some on the right.

The case focuses on a theory known as the “independent state legislature” doctrine advanced by Republican lawmakers in the southern state of North Carolina.

Under the Constitution, the rules for federal elections are set by the state legislature. 

“The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof,” the Elections Clause says.

State legislatures have used their authority to map out congressional districts, set poll hours and agree on rules for voter registration and mail-in ballots.

Their laws have been subject, however, to legal scrutiny by the local courts and possible veto by the state governor. 

No longer, if the North Carolina lawmakers have their way.

In their brief to the nation's highest court, they say the Constitution “sets forth a detailed set of specific rights, specific procedures, and specific allocations of power.

“Here, those carefully drawn lines place the regulation of federal elections in the hands of state legislatures, Congress, and no one else.”

Amy Mason Saharia, a Washington lawyer who has argued a number of cases before the Supreme Court, said it “has never adopted that theory, but it has been floating around for a while” and the conservative-dominated court could embrace it.

‘Reshape American democracy'

North Carolina's Democratic governor Roy Cooper warned that “the court's decision on this alarming argument could fundamentally reshape American democracy.

“Our democracy is a fragile ecosystem that requires checks and balances to survive,” Cooper wrote in an opinion piece published in The New York Times.

“Republican leaders in the North Carolina legislature have shown us how the election process can be manipulated for partisan gain,” Cooper said.

“And that's what you can expect to see from state legislatures across the country if the court reverses course in this case.”

Moore v. Harper stems from an electoral dispute in North Carolina.

The 2020 census found that the state's population had increased, earning it an extra seat in the US House of Representatives.

North Carolina lawmakers redrew the congressional map to add a new district but the state supreme court threw it out in February, arguing that it favored Republicans by grouping Democrats in certain districts, diluting their vote.

A second map was also judged to be unfair and the state high court finally named an independent expert to carry out the redistricting.

North Carolina lawmakers appealed to the Supreme Court arguing that local courts were usurping their authority.

The Supreme Court declined to intervene right away and the map drawn up by the expert was used in November's midterm elections, resulting in seven House members from each party.

‘Nonsense'

Democrats, from the state level to President Joe Biden, law professors and leading civil rights organizations have filed briefs urging the Supreme Court to reject the doctrine.

Sophia Lin Lakin of the American Civil Liberties Union warned of the dangers of an adverse ruling.

“An extreme interpretation of the US Constitution by the Supreme Court in this case will make it even easier for state legislators to suppress the vote, fraud, gerrymander election districts and potentially sabotage election results,” she said.

The Republican Party dismissed the criticism as alarmist.

“Self-anointed constitutional law experts have convinced a healthy cross-section of armchair court watchers that, should the court decide this case the wrong way, it would signal the end of democracy,” the National Republican Committee said in a brief. “Nonsense.”

A number of prominent conservatives did express concern.

“Our political system would suffer harm if partisan gerrymanders were left entirely without state-level checks and balances,” said Arnold Schwarzenegger, the former Republican governor of California.

The court is to deliver its ruling by the end of June.