Is dignity defined by intelligence? What the Smith ruling forces us to answer

Joseph Clifton Smith committed a brutal murder in 1997. He was convicted, sentenced to death, and held on death row for decades. On May 21, 2026, the Supreme Court declined to let Alabama execute him. The reason, at its core, was a number: his IQ falls in the low 70s, close enough to the recognized threshold for intellectual disability that the 11th Circuit Court of Appeals ruled his execution unconstitutional under the Eighth Amendment.

The legal mechanism here traces to Atkins v. Virginia (2002), in which the Supreme Court held that executing persons with intellectual disabilities constitutes cruel and unusual punishment. The justices left the definition of intellectual disability open, noting only that expert opinion at the time placed the cutoff at "an IQ between 70 and 75 or lower." Smith's case spent years cycling through the federal courts — the 11th Circuit ruled in his favor in 2023, the Supreme Court vacated that ruling in 2024, the 11th Circuit ruled in his favor again, and the Supreme Court finally let that second ruling stand.

All of that procedural history circles the same question: does the number on a cognitive test determine what the state may do to a person?

Why courts use IQ at all

The use of IQ as a legal threshold is not arbitrary. Cognitive capacity is genuinely relevant to criminal culpability. A person who cannot fully comprehend the nature and consequences of an act cannot be held fully responsible for it. Moral theology has said this for centuries before clinical psychology gave it a name. Aquinas, analyzing the conditions for a fully voluntary act in the Summa Theologiae, treats ignorance and diminished reason as factors that reduce or eliminate imputability. [^1] The law is trying, clumsily, to honor a real moral distinction.

But here is the problem: once a court draws a line at IQ 70, it has implicitly accepted a premise it has not fully examined. It has suggested that a person with an IQ of 71 occupies a different moral category than a person with an IQ of 69. It has suggested, further, that the person with an IQ of 85 or 100 or 130 has forfeited some protection that the person with an IQ of 68 retains. If the protection is grounded in cognitive capacity, then the logic runs in both directions. Lower IQ means greater protection. Higher IQ means less.

That is a strange place to end up if you believe that human dignity is not a function of intelligence.

What the Catholic tradition actually holds

Theresa Farnan, a philosopher on the Ethics and Public Policy Committee of the National Catholic Partnership on Disability, described Smith's case to EWTN News as "clearly a borderline case" and said that "it's obvious to me he could not grasp the gravity of his crimes." Her observation is a claim about culpability, not a defense of the act. That distinction matters.

But the deeper question Farnan's comment opens is this: what grounds her concern for Smith's life in the first place? Is it that he scored low enough on a test? Or is it something prior to the test?

The Catholic Christian understanding of the person, as articulated through the framework developed by Vitz, Nordling, and Titus, locates human dignity in the imago Dei — the person as created in the image and likeness of God. [^2] That dignity does not scale with IQ. It does not increase with education, decrease with age-related cognitive decline, or evaporate in the presence of a serious crime. It belongs to the person as such, not to the person's capacities. On this account, the reason not to execute Smith is not that he scored 71 rather than 85. It is that he is a human being.

This is not a soft or sentimental position. It is a metaphysical one, and it has sharp teeth. If dignity precedes capacity, then the IQ threshold in Atkins is at best a rough proxy for something the law is trying to protect without being able to name it directly. The law is pointing, however imperfectly, toward a truth its own framework cannot fully articulate.

The problem with using intelligence as a measuring stick

IQ scores carry measurement error. They are sensitive to testing conditions, to cultural context, to the educational history of the person being tested. Clinicians have consistently noted that scores do not fully capture adaptive functioning, emotional regulation, or the social cognition that underlies moral decision-making. A person can score in the mid-70s on a standardized test and demonstrate a range of capacities the test does not reach, and vice versa.

More fundamentally, if a court is prepared to protect a person with an IQ of 69 from execution on the grounds that his cognitive limitations reduce his culpability, it must also reckon with what it is doing when it executes a person with an IQ of 100. That person's greater cognitive capacity does not make his life less valuable. It may make him more culpable for a specific act. But culpability and dignity are not the same thing, and the law risks collapsing them.

CS Lewis, arguing from natural moral law, observed that the content of a moral position and the metaphysical commitments behind it cannot be separated. [^3] You cannot coherently claim that human life deserves protection while grounding that protection in a contingent feature of the person that admits of degrees and can be lost. Either the protection tracks something that does not admit of degrees, or the protection is arbitrary.

The Catholic tradition says the protection tracks being — specifically, being a person made by God. That claim is not falsifiable by a psychometrician. It is prior to measurement.

What this means for how courts should reason

None of this requires that courts abandon cognitive assessment entirely. Diminished capacity is genuinely relevant to culpability, and the law is right to take it seriously. A person who could not grasp the gravity of his act is not the same as a person who planned it in full possession of his faculties. That distinction affects just punishment.

But a coherent account of dignity cannot let cognitive capacity do all the work. If it did, courts would be logically committed to offering less protection to a highly intelligent offender than to a less intelligent one — not just more severe punishment for greater culpability, but less protection as a person. That is not a conclusion a serious theory of rights can accept.

The more defensible position is that dignity grounds a baseline protection that does not vary with IQ, while cognitive capacity remains relevant to the separate question of how culpable a specific person was for a specific act. Courts applying Atkins are reaching, however imperfectly, toward this distinction. Smith's case exposed how fragile the line is when the only tool available is a test score.

Farnan's phrase — that society bears "an even more pronounced" burden "to be radically pro-life" in borderline cases — points toward the precautionary logic that follows from taking dignity seriously. When the consequence of a mistake is irreversible, and when the instrument of measurement is imprecise, the burden of proof should fall on those seeking to end a life, not on those defending it. This applies whether the IQ score is 68 or 88.

Pope Leo XIV has returned repeatedly in the early months of his pontificate to the inadmissibility of capital punishment, building on the 2018 revision to the Catechism that declared the death penalty an attack on human dignity. The argument is not that convicted murderers are innocent. It is that the state does not possess legitimate authority to end a human life when other protective means exist, and that a society serious about the imago Dei will organize its institutions accordingly.

The Smith ruling did not answer the question of whether dignity is defined by intelligence. But the years of litigation it took to reach it, and the narrowness of the ground on which it rests, make the question harder to avoid.

References

[^1]: St. Thomas Aquinas, Summa Contra Gentiles (commentary), p. 555; cf. Summa Theologiae II-II, q. 64, art. 2-3, on how sin and diminished reason affect human culpability and dignity. [^2]: William Nordling, in Vitz, P.C., Nordling, W.J., & Titus, C.S., A Catholic Christian Meta-Model of the Person (2020), pp. 449-472: on the imago Dei as the ground of human dignity independent of capacity or performance. [^3]: CS Lewis, Mere Christianity, p. 20: on the inseparability of moral content from the metaphysical commitments that ground it.