Considerations in Determining Intellectual Disability

Facts of the Case

In July 1997, Thomas Dale Ferguson and four codefendants stole a truck to use as a getaway vehicle for their bank robbery. The truck belonged to Harold Pugh, whom Mr. Ferguson shot. One of Mr. Ferguson’s codefendants shot Mr. Pugh’s 11-year-old son. Both Mr. Pugh and his son died. An Alabama grand jury indicted Mr. Ferguson on four counts of capital murder based on the circumstances of the killing and the age of the younger victim (Ala. Code § 13A-5-40 (a)(2), (10), (15) (1994)). Mr. Ferguson was found guilty on all counts.

During the sentencing phase, Mr. Ferguson presented his low IQ as one of five mitigating circumstances. He called Dr. James Chudy, a clinical psychologist who testified to Mr. Ferguson’s borderline intelligence and personality disorder with borderline features. Mr. Ferguson’s wife also testified that Mr. Ferguson was “mentally slow, and that she made all the decisions in their marriage” (Ferguson, p 1246). Dr. Stephen Rosen, a clinical psychologist called by the state, testified that Mr. Ferguson “was not intellectually disabled despite his IQ score of 69, but [Mr.] Ferguson’s IQ was likely in the borderline range” (Ferguson, p 1247). He also noted Mr. Ferguson to have a personality disorder. The jury recommended a sentence of life in prison without parole. The trial court judge overruled the jury’s vote and sentenced Mr. Ferguson to death.

Mr. Ferguson appealed to the Alabama Court of Criminal Appeals (ACCA) (Ferguson v. State, 814 So. 2d 925 (Ala. Crim. App. 2000)) and to the Alabama Supreme Court (Ex parte Ferguson, 814 So. 2d 970 (Ala. 2001)). Both courts affirmed the ruling.

In 2003, Mr. Ferguson petitioned for a writ of habeas corpus, arguing that as an individual with ID, his death sentence was unconstitutional under Atkins v. Virginia, 536 U.S. 304 (2002). He cited his full-scale IQ scores of 71 in sixth grade and 69 when awaiting trial, as well as details established at trial regarding his limited adaptive functioning. He also raised the concern of ineffective assistance of counsel during pretrial and sentencing. In 2006, the state trial court denied his petition. Mr. Ferguson filed an appeal to the ACCA, which affirmed the denial in 2008. In 2009, the Alabama Supreme Court denied certiorari review. Subsequently, Mr. Ferguson filed a federal habeas petition in the Northern District of Alabama on the abovementioned grounds; the petition was denied in 2014.

Mr. Ferguson requested amendment of judgment regarding the Atkins claim, and the federal district court held an evidentiary hearing on this matter in 2019. Dr. Robert Shaffer, a clinical psychologist, was called after administering the Wechsler Adult Intelligence Scale – Fourth Edition (WAIS-IV) to Mr. Ferguson, who received a full-scale IQ score of 77. Adjusting for the Flynn Effect and applying the standard error of measurement (SEM), the score was determined to be between “69.4 and 78.4 with 95 percent probability, or between 67.9 and 78.9 with a confidence level of 99 percent” (Ferguson, p 1252). The Flynn Effect refers to the phenomenon of upward drift in IQ scores at a rate of approximately .3 points annually (Flynn JR. The mean IQ of Americans: massive gains 1932–1978. Psychological Bulletin. 1984 Jan; 95(1):29–51). Dr. Schaffer used the Vineland Adaptive Behavior Scales Test with Mr. Ferguson’s mother to assess Mr. Ferguson’s adaptive functioning at age 18. Dr. Schaffer concluded that Mr. Ferguson had an ID. Dr. Glen King, a clinical psychologist, was called by the state. On Dr. King’s administration of the WAIS-IV, Mr. Ferguson scored an 85 (range of 81–89, including SEM; the court reduced this score by seven points due to practice effect from readministration of the same test within a five-month period); on administration of the Stanford-Binet Intelligence Test, Fifth Edition (SB-5), he scored 84; on administration of the self-rated Adaptive Behavior Assessment System, Mr. Ferguson rated his ability highly. Based on these and the Independent Living Scales, Dr. King concluded that Mr. Ferguson had neither subaverage intellectual function nor poor adaptive functioning. Upon review of all these findings, the district court denied Mr. Ferguson’s habeas request.

Mr. Ferguson appealed the court’s denial to the U.S. Court of Appeals for the Eleventh Circuit.

Ruling and Reasoning

Mr. Ferguson brought two arguments related to ID and a claim of ineffective counsel before the Eleventh Circuit. Regarding his ID claim, he first raised that Alabama’s standard, which requires demonstration of present substantial deficits in adaptive function, is at odds with Atkins, and therefore unconstitutional. In Atkins, the Supreme Court referenced the “clinical definitions of [intellectual disability requiring] not only subaverage intellectual function, but also significant limitations in adaptive skills” before age 18 (Atkins, p 318). But, individual states were tasked with determining how to uphold and enact these criteria during sentencing. The Alabama Supreme Court interpreted ID broadly in Smith v. State, 213 So. 3d 239 (Ala. 2007), finding that both subaverage intellectual functioning and deficits in adaptive functioning must currently be exhibited, as well as having been present before age 18.

The Eleventh Circuit reasoned that Mr. Ferguson had no history of subaverage intellectual function prior to age 18, and thus met neither Atkins’s nor Alabama’s standard for ID. The appeals court reviewed his IQ scores, including the Flynn Effect and SEM. They reasoned that all of Mr. Ferguson’s scores were above 70 except for two, which the court discounted “based on evidence that [Mr.] Ferguson did not put forth his best effort on those tests” (Ferguson, p 1255). The court thus chose not to address whether Alabama’s standard for determining ID conflicts with Atkins.

Second, Mr. Ferguson argued that the district court erred in omitting the two sub-70 scores and finding him not to be intellectually disabled. He pointed to his other tests, which documented appropriate effort. The appeals court concluded that there was no error in the district court’s selection of which scores to consider, and thus no error in the finding of no ID.

Last, the Eleventh Circuit reviewed the presentencing and penalty phases to rule on Mr. Ferguson’s claim of ineffective counsel. They did not find reasonable probability of deficient performance undermining confidence in the outcome.