A decision issued by the Supreme Court last week featured some of the most significant judicial writing in recent years.

In a 7-2 ruling in Gamble v. United States, the court adhered to a long-standing interpretation of the Fifth Amendment’ protection against multiple prosecutions, or “double jeopardy.” But it is important for many other reasons as well.

The case sparked four separate opinions, each rich in constitutional value.

Justice Clarence Thomas’s concurring opinion focused on whether the Supreme Court should follow precedent or overrule it. It helped to lay the basis for reversing Roe v. Wade, the rogue case that upended abortion laws in all 50 states.

Thomas agreed that for double jeopardy the court should stick by its precedents, thereby following the legal doctrine of stare decisis, which is Latin for “to stand by the decisions.” But Thomas explained there are times to overrule precedent as well.

Stare decisis, Thomas explained, is a principle of common law judging. Common law cases are those where courts develop law in areas where the legislature has not acted. But construing enactments such as the Constitution and statutes is not common law judging. In such cases, the guiding principle is the understanding of the enactors.

Thomas admitted that if the enactment’s language was unclear and an earlier holding interpreted it reasonably, then judges could rightfully follow the earlier holding. On the other hand, if the precedent was clearly wrong, judges had no right to elevate their own decision over the enactors’ understanding.

This has clear implications for Roe v. Wade. The “reasoning” in Roe is almost universally agreed to be dreadful — even by commentators who favor unregulated abortion. So the Thomas analysis sets up Roe for a long-overdue reversal.

Like most other cases this term, the Gamble case debunks a trope repeated ad nauseum by politicians and media on all sides: the claim that the Supreme Court has a “conservative majority.” In Gamble, Justice Samuel Alito — whom the media call “conservative” — wrote the opinion for the court. However, he was joined by three justices more fairly called “liberal.” The two dissenters were (1) Ruth Bader Ginsburg, a liberal, and (2) Neil Gorsuch, commonly pigeonholed as “conservative.” Such mixing is the rule on the present bench, not the exception.

A really impressive aspect of the case is how all the justices used founding-era materials to recover the founders’ understanding of double jeopardy. When I first started working in constitutional law, most writers, including Supreme Court justices, consulted a very limited range of founding-era sources, such as the Federalist Papers and Madison’s notes of the constitutional convention.

I pointed out that the Constitution is a legal document, most of the founders were lawyers, and the 18th century American public was well educated in law. Thus, I argued for also consulting founding-era legal dictionaries, law books, English court cases, and other legal materials. In the Gamble case, all the opinions cite such sources

It is true the justices differ in their conclusions, but this was a particularly hard case. In general, widening the materials consulted creates more certainty than limiting them.

I also have long complained about how legal writers — including the justices — cite documents written decades after the founding as “evidence” of the original understanding. So it was gratifying to see Alito downplaying that practice. He tells us that citing later documents is legitimate only to confirm what we already know from material available during the founders’ own time.

Alito’s opinion touches on the nature of American federalism (“splitting the atom of sovereignty”). And it provides a good response to liberal academics who claim the Constitution’s Commerce and Necessary and Proper Clauses granted Congress almost unlimited power. They argue that the Constitution’s drafters intended those clauses to reflect a very broad provision from an earlier draft (the Virginia Plan).

In Gamble, Justice Alito tells us, “The private intent behind a drafter’s rejection of one version of a text is shoddy evidence of the public meaning of an altogether different text.”

Several justices make unfavorable reference to Congress’s massive intrusion into ordinary criminal law. When considering the Constitution, Americans were told repeatedly that except for a very few offenses such as treason, criminal law would be a state concern and outside the power of Congress. Perhaps in some future case, the court will curb this congressional intrusion.

Rob Natelson is senior fellow in Constitutional Jurisprudence at the Independence Institute in Denver. While teaching constitutional law at the University of Montana, he worked to popularize the use of 18th century law in constitutional research. He is the author of The Original Constitution: What It Actually Said and Meant (3rd ed. 2015).