This morning, the Supreme Court decided to hear Moore v. Harper, a challenge to the congressional maps in North Carolina that has the potential to upend over 200 years of election law. In Moore, members of the state legislature are urging the Supreme Court to reinstate the map they drew – and that North Carolina courts struck down as unconstitutional and redrew – using what is known as the “independent state legislature” theory (or ISL). That theory claims that the federal Constitution gives state legislatures the power to regulate federal elections without checks from other state officials or constraints from the state’s constitution. Though Moore concerns congressional redistricting, the ISL theory reaches far further and would have sweeping and dangerous implications for most aspects of federal elections.

In 2020, Justices Clarence Thomas, Samuel Alito, Neil Gorsuch and, at times, Brett Kavanaugh all indicated that they would have adopted the theory and its vast consequences on the emergency docket. These justices are all part of the Court’s “originalist” faction.   Originalists, like these four justices and Justice Amy Coney Barrett, contend that constitutional provisions mean what they meant to the public that adopted them. As Justice Barrett has explained, originalists “care about what people understood words to mean at the time that the law was enacted because those people had the authority to make law.”

Since 2020, however, new historical research has emerged that puts the ISL theory at odds with the original public meaning of the Constitution. Though all eyes will be on Justice Barrett, who has not yet opined on the theory, Moore also offers the rare opportunity for Justices Thomas, Alito, Gorsuch, and Kavanaugh to show the principled nature of their commitment to originalism by updating their views in light of new Founding-era historical analysis.

Defining the Independent State Legislature Theory

The ISL theory is really multiple overlapping theories that fall within the broad name. The crux of any version of the theory is that the federal Constitution’s mention of state “legislatures” in the Elections and Electors Clauses should be understood as a grant of sole authority to state legislatures in setting the rules for congressional and presidential elections, respectively. In some versions, that means a state legislature’s regulation of federal elections could not be struck down by a state court on state constitutional grounds – the exact scenario at issue in Moore. The Moore petitioners go further and claim that, under the theory, a state legislature may not even delegate power to other state actors, like courts or election officials, to implement state election law where the legislature fails to address an issue.

Under some other versions of the theory not at issue in Moore, governors could not veto state laws concerning federal elections, nor could citizens, by ballot initiative, change the rules for federal elections. Proponents of this version of the theory read the reference to “legislature” to mean only state assemblies and state senates (sometimes called “institutional” or “formal” legislatures) and not the broader legislative processes, such as gubernatorial veto or citizen ballot initiative, used by a state. And, while the Supreme Court has never adopted the theory, in Bush v. Gore, Chief Justice William Rehnquist, joined by Justices Antonin Scalia and Clarence Thomas, advanced a version of the theory that would allow federal courts to step in and block state court interpretations of state law where the federal courts found those interpretations to diverge too much from the plain text.

Any or all of these versions of the ISL theory promise to be hugely disruptive to federal elections. Laws struck down under state constitutions or revised by ballot initiative could be revived for federal elections, resulting in the disenfranchisement of countless voters. And, because ISL would not have any effect on the rules governing state elections, administrators and voters would need to comply with two different and potentially conflicting sets of rules for federal and state elections simultaneously. That chaos, in turn, may make it easier to gin up false claims of election fraud and so make it easier for politicians to mess with vote counts or wrongfully refuse to certify election results.

It is worth a quick pause, however, to clarify what the independent state legislature theory is not. Through the January 6th Committee hearings, we are learning more about Trump’s effort in 2020 to have state legislatures overturn the will of their voters and appoint their own preferred slate of electors. Although the theory underpinning that effort claimed that state legislators had a gobsmacking amount of power, the independent state legislature theory – even in its most maximalist form – would not give state legislatures the right to veto their voters’ choices. That is because, under the ISL theory in all of its forms, state legislatures must still comply with federal law, including the many federal and constitutional provisions that set the framework for federal elections, guarantee voting rights, and prohibit arbitrariness and discrimination in the counting of ballots.

Debunking the Independent State Legislature Theory

On, then, to the merits of the theory and, in particular, the Constitution’s text. The proponents of the theory rest their argument primarily on the fact that the Elections and Electors Clauses of the Constitution refer to “legislatures” as opposed to “states” as the entities that regulate federal elections. This use of “legislature,” according to the theory’s proponents, therefore means that only the legislature, and not other state-level actors, is empowered to regulate federal elections. But the singling out of a single word without looking to the broader context of the constitution or the historical context of its enactment is exactly the kind of “literalism [that] strips language of its context” that Justice Barrett decried as an academic. A contextual reading of these clauses plainly rebuts the ISL theory.

Start with “legislature.” At a basic definitional level, the term “legislature” requires reference to the state constitution that creates it. Is the “legislature” bi- or unicameral? How many people, with what qualifications sit in it? Answering those basic questions requires incorporating state constitutions’ definitions of each state’s legislature. The theory’s proponents thus are asking the Court’s textualists to read the word “legislature” to mean “as defined by some, but not all, of the state’s constitution’s provisions.” Moreover, the Framers generally said so when they wanted to give a branch unreviewable power. See, e.g., Art. I, § 2 (“The House of Representatives shall choose their speaker and other officers; and shall have the sole power of impeachment.” (emphasis added)). Adopting ISL thus reads “sole” into the text where the framers kept it out.

That implausible reading is all the more improbable when considered in light of the Founding-era historical context. As Vikram Amar and Akhil Amar explain in a 2022 article, at the Founding, “the public meaning of state ‘legislature’ was clear and well accepted . . . : A state ‘legislature’ was . . . an entity created and constrained by its state constitution.”  Unsurprisingly, then, as Hayward Smith explains in his own 2022 article, in the decade after ratification of the federal Constitution, every state except South Carolina to have had a constitutional convention adopted state constitutional provisions regulating federal elections. That choice makes no sense if the Founding-era generation understood the federal Constitution to bar state constitutions from doing so.  And more recent historical scholarship, this time from Eliza Sweren-Becker and Michael Waldman, explains why state constitutional constraints on state legislatures regulating federal were so universally adopted: the founding generation were concerned that self-interested partisans would “twist[] election rules to benefit their faction.”  Were there any ambiguity in early state practice, Michael Weingartner’s 2021 piece shows that, since the Founding, across the country, “state constitutions have regulated both the procedure and substance of federal elections” and “state courts [have] consistently reviewed laws regulating federal elections.”

And the Supreme Court has repeatedly rejected the ISL theory when upholding this kind of state regulation. Over a century ago, in Ohio ex rel. Davis v. Hildebrant, the Supreme Court held that the Elections Clause’s reference to “Legislature” is to “the legislative power” of a state, which contains “the state Constitution and laws.” So, too, in Smiley v. Holm, where the Supreme Court held that legislative action under the Elections Clause must be made “in accordance with the method which the state has prescribed for legislative enactments,” including the state’s constitution. As recently as 2015, in Arizona State Legislature v. Arizona Independent Redistricting Commission, the Supreme Court rejected ISL by upholding the use of independent redistricting commissions – bodies that are decidedly not the “legislature” – for federal congressional elections. And, in 2019, in Rucho v. Common Cause, all nine justices agreed that state constitutions could be used as a check on partisan gerrymandering in congressional elections. Adopting the ISL theory is thus at odds with more than a hundred years of Supreme Court precedent and would disrupt whole bodies of law written by state legislatures and reviewed by state courts relying on that precedent.

The momentum to adopt ISL – and upend this unbroken line of precedent and related state practice – began building in 2020, when Justices Alito, Gorsuch, Thomas and, at times, Kavanaugh all signaled a desire to do so in various cases concerning the 2020 election. But new arguments and scholarship have demonstrated that doing so would be inconsistent with the original meaning of the Constitution. And that should doom the theory. As Justice Barrett explained in her confirmation hearings, as an originalist, she views the Constitution’s meaning as fixed at the time of ratification. It “doesn’t change over time and it’s not up to me to update it or infuse my own policy views into it.” Through that lens, the modern effort to inject ISL theory into constitutional doctrine should horrify Justice Barrett and the Court’s other originalists. All eyes will be on the Court to see whether she and the other conservative justices now live up to the principles of “originalism” they have professed.