The Rational Basis Test Is an Unconstitutional Kludge

Courts created the 'Rational Basis' test in Century XIX so activist judges can exercise final authority over issues which the U.S. Constitution does not grant to them.  An example of the Rational Basis test applied to health care controversies is Abigail Alliance for Better Access to Developmental Drugs v. FDA, in which the D.C. Circuit prevented terminally ill cancer patients from accessing potentially lifesaving experimental drugs.

Clark Neily, senior vice president for legal studies at the Cato Institute, challenges the use of the Rational Basis test:

https://www.cato.org/blog/rational-basis-test-unconstitutional-kludge

The Rational Basis Test Is an Unconstitutional Kludge
By Clark Neily - February 27, 2025

Like Captain Ahab chasing Moby Dick, I’ve sworn eternal hostility to the rational basis test. It’s a fraud and a charade—a constitutional kludge dressed up as judicial review, but with none of the substance. Worse, it’s unconstitutional for two reasons we’ll get to in a moment.

Before supporting my extraordinary claim that the Supreme Court’s default standard for deciding constitutional cases is itself unconstitutional, it’s worth briefly noting some of the absurd and pernicious results the rational basis test has produced. Most law students know the 2005 eminent-domain case Kelo v. City of New London, and they also know to put plenty of stink on the word “Kelo” when they say it because it authorized the forced condemnation and bulldozing of an entire working-class neighborhood so Pfizer and New London could replace it with Yuppieville (which they never actually did).

But not as many people have heard of Abigail Alliance for Better Access to Developmental Drugs v. FDA, in which the en banc D.C. Circuit found a rational basis for preventing terminally ill cancer patients from accessing potentially lifesaving experimental drugs. Thus, if someone tries to tell you that rational basis review “only” implicates economic regulations like the baking of bread or the selling of flowers, feel free to throw dying cancer patients or adoption-seeking children in their face.

These cases aren’t just outliers—they’re symptoms of a deeper flaw. As I have argued at length elsewhere, the rational basis test, the Supreme Court’s go-to for most constitutional challenges, is itself unconstitutional. Here’s why.

Rational Basis Review Is Not an Exercise of the “Judicial Power”

Article III of the Constitution vests the “judicial power” in the federal courts. Although not explicitly defined in the text, this phrasing indicates that judges are empowered to resolve legal disputes through the exercise of judgment. When judges decide cases using methods that don’t involve genuine judgment, they exceed their constitutional authority.

Historically, legal disputes were sometimes resolved through mechanisms like trial by combat or trial by ordeal—methods that involved no actual judgment. The Constitution deliberately moved away from such approaches by specifically vesting “judicial power” in the courts, requiring the exercise of reasoned judgment in deciding cases.

The most deferential form of rational basis review—where courts uphold laws if there is any conceivable justification for them, even one not articulated by the government—functionally abandons judicial judgment. It replaces actual scrutiny with automatic deference, transforming judicial review from a meaningful check on government power into a hollow ritual with a predetermined outcome.

This abandonment of judgment was starkly illustrated in an exchange during oral arguments in Alaska Central Express Inc. v. US (9th Cir. 2005), where Judge William Fletcher questioned a Department of Justice lawyer about the limits of the “any conceivable basis” standard:

Judge Fletcher: Can I get at your definition of “conceivable?” To take an outer-boundary sort of example.… Is it conceivable that space aliens are visiting this planet in invisible and undetectable craft?

Mr. Yellin: Is it conceivable?

Judge Fletcher: That’s my question.

Mr. Yellin: Yes, it’s conceivable.

Judge Fletcher: And that would be a basis for sustaining congressional legislation, if … the person sponsoring the bill said, “Space aliens are visiting us in invisible and undetectable craft, and that’s the basis for my legislation,” we can’t touch it?

Mr. Yellin: If Congress made a finding of that sort?

Judge Fletcher: That’s my question.

Mr. Yellin: Your Honor, I think if Congress made a finding of that sort, I think, Your Honor, it would not be appropriate for this Court to second guess that.

Judge Fletcher: OK, in other words, “conceivable” is “any piece of nonsense is enough.”

Mr. Yellin: Your Honor, I don’t think … It is largely unbounded. It is not completely unbounded.

Judge Fletcher: How can you say it’s not completely unbounded when you agreed with my absolutely preposterous example of what’s conceivable?

This exchange powerfully demonstrates how the rational basis test can require judges to accept justifications that are patently absurd. If judges must defer to even “preposterous” legislative rationales like invisible aliens, they aren’t really exercising any judgment at all; instead, they’re reflexively rubber-stamping government action, which cannot be what the Constitution means by “judicial power.”

Requiring Judges to Invent Justifications for Potentially Unconstitutional Laws Turns Them into Courtroom Advocates for Government

Perhaps even more troubling is another aspect of the most deferential form of rational basis review: Courts have repeatedly stated that judges must hypothesize conceivable justifications for government action if the ones advanced by the government prove inadequate. This effectively forces judges to serve as advocates for the government while simultaneously acting as impartial adjudicators in the same case.

If that seems dubious or even hyperbolic, consider this passage from the majority opinion of a case called Powers v. Harris that I tried and argued involving an Oklahoma law that made it a crime for anyone but state-licensed funeral directors to sell caskets. When the government’s rationalizations prove wanting, judges “are not bound by [its] arguments as to what legitimate state interests the statute seeks to further. In fact, this Court is obligated to seek out other conceivable reasons for validating” the challenged law. The majority then doubled down by adding a footnote with a string cite of other opinions to the same effect, including one in which the author noted that “we resort to our own talents and those of counsel to discern the rationality of the classification in question.”

Consider how this would appear in any other context: Imagine a judge presiding over a contract dispute between a private company and a government agency who announces before trial, “I must advise you that I have a legal duty in this case to help the government come up with justifications for its alleged breach of contract. But I want to assure you that I will only do so if necessary to help the government prevail.”

Such judicial conduct would obviously violate fundamental principles of procedural fairness and due process. Yet this is precisely what the rational basis test requires in constitutional cases. Judges are duty-bound to devise post-hoc rationalizations for government action, fundamentally compromising their role as neutral arbiters.

This violates the Fifth and Fourteenth Amendments’ guarantees of due process—a proceeding where the judge actively assists one side cannot provide the “process that is due” to the challenging party. It also undermines the adversarial system upon which our constitutional structure depends, where parties present their best arguments and judges impartially evaluate them.

Some might object that the rational basis test cannot be unconstitutional because it was created by the Supreme Court, which has the final word on constitutional interpretation. However, the Court’s authority to interpret the Constitution doesn’t make all its interpretations correct. Throughout history, the Court has created doctrines it later recognized as erroneous and unconstitutional—from Plessy v. Ferguson’s “separate but equal” to Korematsu’s approval of Japanese internment.

Moreover, the rational basis test is not a single, consistent doctrine. As we recently explained in this amicus brief in support of an unsuccessful cert petition involving Wisconsin’s discriminatory child-adoption law, “like coffee, athletes, and beer, the rational basis test comes in different strengths”—that is, a whole spectrum of purportedly rational-basis standards, from the functional rubber-stamp of the “any conceivable basis” version to “rational basis with bite,” which requires at least plausible justifications supported by evidence.

By requiring no actual exercise of judgment and casting judges as government advocates, the rational basis test reduces judicial review to what my non-lawyer wife brilliantly described as a rigged carnival game, peddling the appearance of fairness while ensuring that the house wins even when it shouldn’t.

So there you have it. The endlessly permissive rational basis test doesn’t just enable judges to have their constitutional cake and eat it too by proclaiming the existence of rights they have no real intention of protecting—it even violates the very Constitution of which it makes such a mockery.