A phrase that decides a great many American constitutional cases is “deeply rooted in this Nation’s history and tradition”. It appeared again this month, when the Fifth Circuit used it to hold that there is no constitutional right to clean drinking water.

It is worth understanding, because it determines which claims can be constitutional claims at all.

The problem the test exists to solve

The Fourteenth Amendment says no state shall deprive any person of life, liberty or property without due process of law. Read narrowly, that is a promise about procedure: the government must follow fair steps before taking something from you.

American courts have long read it to do more — to protect certain freedoms from government interference regardless of the procedure used. This is called substantive due process, and it is the doctrinal home of a series of well-known rights that are not written in the constitutional text.

That immediately raises a question with no obvious answer: which unwritten rights count? Without some limiting principle, judges could recognise whatever they personally believed important, which is a considerable amount of power for unelected officials.

The answer the courts settled on

The test that emerged asks whether the asserted right is deeply rooted in the nation’s history and tradition, and implicit in the concept of ordered liberty. If it is, it receives constitutional protection. If not, it does not.

In practice this means looking backwards: at founding-era practice, at nineteenth-century state laws, at what was regulated or protected when the relevant amendments were adopted. A court asks not whether something is important now, but whether it was treated as a protected liberty then.

This is why the Jackson case turned on history rather than on lead levels. Once the test is framed that way, the question becomes whether Americans in the eighteenth or nineteenth century recognised a constitutional entitlement to municipal water quality — and municipal water systems of the modern kind did not exist.

The case for it

Defenders of the test, who include a majority of the current Supreme Court, make a democratic argument.

A constitutional right is permanent in a way legislation is not. Recognising one removes the question from ordinary politics, where it could be debated, amended and revisited. Judges doing that on the strength of their own moral judgement are substituting themselves for the electorate.

The history test provides an external constraint: something a judge can be shown to have got wrong, rather than a preference they can simply assert. And it leaves everything else to legislatures, which can act faster and can change their minds.

The case against

Critics make three arguments, and they are not merely political.

The first is that history is less determinate than the test assumes. Deciding what was deeply rooted requires choosing which sources count, at what level of generality to describe the right, and which period to examine. Those choices frequently determine the outcome, which means the constraint is looser than it appears.

The second is about who was making the history. The traditions of the eighteenth and nineteenth centuries were established by a polity that excluded most of the population from participation. A test that treats those traditions as the measure of liberty embeds those exclusions.

The third is the one the water case illustrates: it cannot accommodate harms that did not exist historically. Novel dangers arrive with new technology and new forms of state provision, and a backward-looking test has no way to reach them.

What it means for reading a ruling

Two things worth carrying.

A holding that something is not a constitutional right is not a holding that it does not matter, is not harmful, or cannot be regulated. It is a statement about which body decides. Almost every protection people actually rely on day to day — clean water standards included — comes from statutes and regulators, not from the Constitution.

And the level of generality at which a right is described often decides the case before the history is examined. “A right to bodily integrity” and “a right to uncontaminated municipal water” are different questions with different historical records, and choosing between them is where much of the real judging happens.

Sources

• Majority opinion of Judge Kurt Engelhardt, en banc US Court of Appeals for the Fifth Circuit, 4 September 2026
• Fourteenth Amendment to the United States Constitution
• Established Supreme Court doctrine on substantive due process and the history-and-tradition standard
• Published legal scholarship on levels of generality in substantive due process analysis