Cite as: 600 U. S. ____ (2023)
9
Opinion of the Court
future state-court proceedings.” Id., at 480.
Harper I fits within this second category of cases described in Cox Broadcasting. By striking down the 2021
congressional plans enacted by the General Assembly, Harper I “finally decided” the “federal issue” whether the Elections Clause insulates state legislatures from review by
state courts for compliance with state law. See 380 N. C.,
at 390–391, 868 S. E. 2d, at 551–552. That issue both has
survived and requires decision because subsequent proceedings have neither altered Harper I ’s analysis of the federal issue nor negated the effect of its judgment striking
down the 2021 plans. In its decision “overruling” Harper I,
the North Carolina Supreme Court in fact reaffirmed that
it retains the authority to review congressional districting
plans for compliance with state law. Harper, ___ N. C., at
___, 886 S. E. 2d, at 422.
That the North Carolina Supreme Court overruled Harper I does not affect the judgment in that case for purposes
of §1257(a). “[T]he res judicata consequences of a final, unappealed judgment on the merits” are not “altered by the
fact that the judgment may have been wrong or rested on a
legal principle subsequently overruled in another case.”
Federated Department Stores, Inc. v. Moitie, 452 U. S. 394,
398 (1981). The North Carolina Supreme Court has said
much the same. East Carolina Lumber Co. v. West, 247
N. C. 699, 701, 102 S. E. 2d, 248, 249 (1958) (“An erroneous
or irregular judgment binds the parties thereto until corrected in a proper manner.”). That Court did not purport to
alter or amend in any way the judgment in Harper I. In
short, the record before us shows that Harper I “finally decided” the Elections Clause issue, which has survived subsequent proceedings in the North Carolina Supreme Court
such that it continues to “require decision” by this Court.
Cox Broadcasting, 420 U. S., at 480.
JUSTICE THOMAS sees it differently. He correctly ob-