Hall v. Florida, 572 U.S. ___ (2014), was a United States Supreme Court case in which the Court held that a bright-line IQ threshold requirement for determining whether someone has an intellectual disability (formerly mental retardation) is unconstitutional in deciding whether they are eligible for the death penalty.
The case fleshed out standards first announced by the Court in Atkins v. Virginia, which left the determination of what constitutes intellectual disability to the states. In Atkins, the Court held that people are intellectually disabled and thus ineligible for the death penalty if these three conditions are met: 1.) “subaverage intellectual functioning,” meaning low I.Q. scores; 2.) a lack of fundamental social and practical skills; and 3.) the presence of both conditions before age 18. The Atkins court stated I.Q. scores under “approximately 70” typically indicate disability, but the court let the states determine who is mentally disabled and thus cannot be executed.
In Hall the Court narrowed the discretion under which U.S. states can designate an individual convicted of murder as too intellectually incapacitated to be executed. The Court prohibited states in borderline cases from relying only on intelligence test scores to determine whether a death row inmate is eligible to be executed. States must look beyond IQ scores when inmate tests are in the range of 70 to 75. IQ tests have a margin of error, and those inmates whose scores fall within the margin must be allowed to present other evidence of mental disability. The Court further held that the states may not use a "rigid rule" that denies leniency to defendants with severe mental disabilities simply because they score above 70 on an IQ test. Hall had scored a 71 instead of 70 on an I.Q. test. Justice Anthony M. Kennedy wrote for the majority that this "rigid rule, the court now holds, creates an unacceptable risk that persons with an intellectual disability will be executed, and thus is unconstitutional." If an individual claiming intellectual incapacity has an IQ score that falls somewhere between 70 and 75, then that individual’s lawyers must be allowed to offer additional clinical evidence of intellectual deficit, including, most importantly, the inability to learn basic skills and adapt to changing circumstances.
The court also adopted the term "intellectually disability" to replace "mentally retarded," which had been used in prior opinions. Intellectually disability is a condition characterized by significant limitations in both intellectual functioning and in adaptive behavior, which covers many everyday social and practical skills, and originates before the age of 18, according to the American Association on Intellectual and Developmental Disabilities, and the term is preferred by the medical profession.