Washington, DC (CBS) - The Supreme Court is hearing an appeal from a Florida death row inmate who claims he is protected from execution because he is mentally disabled.
The case being argued Monday at the court centers on how authorities determine who is eligible to be put to death, 12 years after the justices prohibited the execution of the mentally disabled.
The court has until now left it to the states to set rules for judging who is mentally disabled. In Florida and certain other states, an intelligence test score higher than 70 means an inmate is not mentally disabled, even if other evidence indicates he is.
Inmate Freddie Lee Hall has scored above 70 on most of the IQ tests he has taken since 1968 but says ample evidence shows he is mentally disabled.
A judge in an earlier phase of the case concluded Hall "had been mentally retarded his entire life." Psychiatrists and other medical professionals who examined him said he is mentally disabled.
As far back as the 1950s, Hall was considered "mentally retarded" - then the commonly accepted term for mental disability - according to school records submitted to the Supreme Court.
He was sentenced to death for murdering Karol Hurst, a 21-year-old pregnant woman who was abducted leaving a Florida grocery store in 1978.
Hall also has been convicted of killing a sheriff's deputy and has been imprisoned for the past 35 years. He served a prison term earlier for assault with intent to commit rape and was out on parole when he killed Hurst.
Hall's guilt is not at issue before the high court.
The Florida Supreme Court has ruled that the state law regarding executions and mental disability has no wiggle room if an inmate tests above 70.
Psychiatrists and psychologists who are supporting Hall say an IQ test alone is insufficient for a diagnosis of mental disability. They say there's a consensus among the mental health professions that accurate diagnosis must also include evaluating an individual's ability to function in society, along with finding that the mental disability began in childhood.
They and Hall also contend that an IQ score is properly read in a range because the results are generally reliable, but not 100 percent so. The range takes into account a margin of error, a feature of all standardized testing.
The case is Hall v. Florida, 12-10882.