Alternative Testing May Not be Substituted for IQ Testing in the Mental Retardation Claim of Death Row Inmate

Yokamon Laneal Hearn was sentenced to death for the carjacking and fatal shooting of a Dallas-area stockbroker in 1998.  His initial execution date was set for March 4th, 2004, but it was stayed due to his claim of mental retardation.  In an application for Writ of Habeas Corpus to the Texas Court of Criminal Appeals, Hearn asserts that he is mentally retarded and, pursuant to the Supreme Court holding in Atkins v. Virginia, 536 U.S. 304 (2002), constitutionally exempt from execution.

According to Texas statutes and caselaw, mental retardation is defined by:

(1) significantly subaverage general intellectual functioning; (2) accompanied by related limitation in adaptive functioning; (3) the onset of which occurs prior to the age of 18.

Under the DSM-IV, the first prong (significantly subaverage general intellectual functioning) is defined as an IQ of about 70 or below (with a 5 point margin of error).  In this case, Hearn was administered several IQ tests, both by the State and the defense.  His scores ranged from 74 to 93, and it could not be clearly established that his IQ was about 70 or below.  As such, he searched for an alternative in order to establish subaverage intellectual functioning.

To support his claim of mental retardation, Hearn attempts to use neuropsychological measures to wholly replace full-scale IQ scores in measuring intellectual functioning.  The doctor who performed the testing testified that:

Neuropsychological testing, together with the diagnosis of fetal alcohol syndrome, has demonstrated that the significant limitations I have identified in Mr. Hearn's adaptive behavior are, nevertheless, a product of intellectual deficits...I am satisfied that Mr. Hearn has mental retardation.

The Court of Criminal Appeals, however, is not yet willing to accept new testing measures for mental retardation:

We hold that alternative assessment measures can not be substituted for full-scale IQ scores.

The Court notes in its opinion that its guidelines are judicially created because the Texas Legislature has yet to enact guidelines for enforcing the Supreme Court's Atkins mandate.  So, unless and until, the legislature decides to take up the issue, a full-scale IQ score of about 70 (give or take 5) is what will get your foot in the door.  Anything less, regardless of what other testing may reveal, and the application will be dismissed.

There is no news yet about a future execution date for Hearn.

See CCA opinion HERE.