If the court rules in favor of the legal theory being advanced, then state legislatures would have unfettered ability to ignore state constitutions, state laws, and state courts, and to exclude the Governor or independent agencies from making election administration rules relevant to federal elections.
Independent Congressional district redistricting commissions in states that have them would be rendered unconstitutional, giving state legislatures in those states (without having to follow the usually process of approving laws including the Governor's veto power) a chance to redraw electoral boundaries in a patently and openly partisan interest maximizing manner (subject only to federal constitutional restrictions requiring, for example, the districts have equal population, be contiguous and be compact, and the federal statutory requirement that they be single member districts which conduct federal elections on the first Tuesday after the first Monday in November in even numbered years). Review of these districts under federal law would be limited to the federal courts.
As Amy Howe explains at SCOTUS Blog:
The Supreme Court will take up a case from North Carolina next term
that could upend federal elections by eliminating virtually all
oversight of those elections by state courts. On Thursday, the
justices granted review in Moore v. Harper, a dispute arising from
the state’s efforts to draw new congressional maps in response to the
2020 census.
The doctrine at the heart of the case is known as the “independent
state legislature” theory – the idea that, under the Constitution,
only the legislature has the power to regulate federal elections,
without interference from state courts. Proponents of the theory point
to the Constitution’s elections clause, which gives state legislatures
the power to set the “Times, Places and Manner of holding Elections
for Senators and Representatives.”
Then-Chief Justice William Rehnquist was an early proponent of the
theory. In a concurring opinion in Bush v. Gore, the 2000 case that
halted the recount in Florida in the presidential election, Rehnquist
(in an opinion joined by Justices Antonin Scalia and Clarence Thomas)
outlined his view that the state court’s recount conflicted with the
deadlines set by the state legislature for the election.
The issue returned to the Supreme Court in 2020, when the justices
turned down a request by Pennsylvania Republicans to fast-track their
challenge to a Pennsylvania Supreme Court ruling that required state
election officials to count mail-in ballots received within three days
of Election Day. In an opinion that accompanied the court’s order,
Justice Samuel Alito (joined by Justices Clarence Thomas and Neil
Gorsuch) suggested that the state supreme court’s decision to extend
the deadline for counting ballots likely violated the Constitution.
After the Republican-controlled North Carolina legislature adopted a
new congressional map in early November 2021, a group of Democratic
voters and non-profits went to state court to challenge the map. They
contended among other things that, because the state is roughly
divided between Democrats, Republicans, and unaffiliated voters, the
new map – which likely would have allowed Republicans to pick up two
more seats in Congress, giving them as many as 10 of the state’s 14
seats – was a partisan gerrymander that violated the state’s
constitution.
In February 2022, the North Carolina Supreme Court blocked the state
from using the map in the 2022 elections and ordered the trial court
to either approve or adopt a new map before the end of the month. The
trial court adopted a new map, drawn by three experts appointed by the
court.
Republican state legislators came to the Supreme Court on an emergency
basis in late February, asking the justices to reinstate the
legislature’s original map before the state’s primary election, which
took place on May 17. But over a dissent by Alito that was again
joined by Thomas and Gorsuch, the court turned down the request. Both
the Alito dissent and a concurring opinion by Justice Brett Kavanaugh,
however, called the “independent state legislature” theory an
important question, with Alito adding that the justices “will have to
resolve this question sooner or later, and the sooner we do so, the
better.”
The legislators returned to the court later in March, seeking review
of the North Carolina Supreme court’s decision invalidating the
legislature’s map and ordering a new map for the 2022 elections. They
told the justices that the state supreme court’s order was “starkly
contrary to the” elections clause. The text of that clause, the
legislators insisted “creates the power to regulate the times, places,
and manner of federal elections and then vests that power in ‘the
Legislature’ of each State.” The “independent state legislature”
question, the legislators stressed “‘is almost certain to keep arising
until the Court definitively resolves it.’” And because North Carolina
will use the map created by the court for its 2022 congressional
elections, they continued, the justices should resolve the question in
this case, rather than having to do it on an expedited basis in a
dispute arising after an election has already occurred.
State officials countered that the North Carolina dispute would not
resolve the “independent state legislature” question at all, because
the state legislature had specifically given the state’s courts the
power to impose a temporary redistricting plan – just as the North
Carolina Supreme Court did in this case.
