Atkins & The IQ Fallacy: Why IQ is Not a Reliable Measure of Culpability (with Dr. Ted Lidsky)

The Supreme Court determined that individuals with intellectual disabilities are less culpable and should not face capital punishment.  Diminished Capacity is also applied in non-capital sentencings. In Hamm v. Smith, the Supreme Court is revisiting the 70 IQ cutoff because of new understandings about errors in measurement. But the bigger problem is IQ tests fail to measure key cognitive deficits tied directly to moral and criminal responsibility.   Therefore, it's time for courts to move beyond IQ as the sole measure of brain functioning.   IN THIS EPISODE: Five misconceptions about whether IQ is a valid reflection of impaired cognitive functioning; A list of all cognitive deficits IQ tests do NOT measure; "The Practice Effect" and other measurement errors in IQ testing; Atkins in the context of Autism – the rationale for Atkins is the same, but the standard is useless; The curious case of Phineas Gage – frontal lobe damage doesn't always impact IQ; Traumatic brain injury doesn't always impact IQ; The right testing to measure cognitive deficits.   CONTACT INFO FOR DR. LIDSKY:   732-580-6157  |  [email protected]   LINKS: A deep dive into Hamm v. Smith on Scotus Blog:   https://www.scotusblog.com/2025/12/hamm-v-smith-and-the-future-of-capital-punishment/   Other Set for Sentencing Ep. with Dr. Ted Lidsky:  Ep. 81:  A Child's Poison