VOL. 126 | NO. 71 | Tuesday, April 12, 2011
IQ Use in Death Penalty Ruled On
By Bill Dries
The Tennessee Supreme Court Monday set new standards in death penalty cases for determining whether a defendant was intellectually disabled at the time of the crime.
The ruling in the Memphis-based case of Michael Angelo Coleman affects the application of the death penalty in Tennessee, where by law, those who are intellectually disabled cannot be executed.
Coleman is on death row for the 1979 murder in Memphis of Leon Watson. Watson was robbed and killed by Coleman and Michael Anthony Bell. Coleman, convicted of six prior violent felonies, admitted he was the person who shot and robbed Watson.
The trial court and an appeals court held that Watson’s score on an intelligence quotient test, or IQ test, made the case for imposing the death penalty. The court and the law use “intellectual disability” to refer to a set of disabilities that affect how a person functions and the disabilities usually originate at or near birth.
The Tennessee Supreme Court disagreed and remanded the case for a rehearing on Coleman’s intellectual ability.
“We have determined that the plain language of (Tennessee law) does not limit to raw test scores the evidence regarding whether a criminal defendant is a person with intellectual disability,” wrote Justice William C. Koch Jr. in the opinion.
The court ruled Tennessee legislators were clear in making the law different than laws in other states that make the IQ test score the basis for the death penalty.
“Ascertaining a person’s IQ is not a matter within the common knowledge of laypersons. Expert testimony in some form will generally be required to assist the trial court in determining whether a criminal defendant is a person with intellectual disability,” Koch wrote, adding the trial court isn’t required to follow the opinion of an expert but must give it “full and fair consideration.”
“Our interpretation of (state law) is consistent with the current clinical approach to the diagnosis and assessment of intellectual disability and with current practice reflected in a number of Tennessee cases where the parties themselves have taken issue with the validity and weight of raw scores of intelligence tests.”
The U.S. Supreme Court has left the question of a standard for determining intellectual disability to states.
Koch wrote that lower courts have interpreted those four rulings to mean there is a “mandatory requirement that only raw IQ test scores may be used to determine whether a criminal defendant” is impaired enough to decide whether the death penalty can be sought. The IQ test score for seeking the death penalty was interpreted as being anything greater than 70.
Coleman met that standard for imposing the death penalty, but two experts testified he was intellectually disabled.