What happens to a society in which judicial practice becomes unmoored from reasonable standards of evidence? How does a just society treat people with intellectual disabilities?
These are among the questions before us in Missouri’s Oct. 5 planned execution of Ernest Johnson. Johnson was convicted of the brutal 1994 murders of Mabel Scruggs, Fred Jones and Mary Bratcher in a botched armed robbery of a Casey’s General Store in Columbia. We remember the suffering of the victims and their families and grieve deeply for the loss of these three members of our Columbia community.
Johnson’s guilt is not in question, and it is reasonable that he spend life in prison for these crimes, but to carry out this execution would violate the Eighth Amendment prohibition on cruel and unusual punishment because of extensive evidence that he has an intellectual disability.
The U.S. Supreme Court ruled in its 2002 Atkins v. Virginia decision that executing a person with intellectual disability constitutes cruel and unusual punishment. However, states are allowed to define their own standards to determine intellectual disability, and Missouri prosecutors employed a process that would not pass muster in any reasonable intellectual assessment.
On the night of the murders, Johnson had been using crack cocaine and planned to rob the convenience store to fuel his habit. He was arrested the next day and was found guilty of the murders.
In a 2005 resentencing trial convened after the Atkins decision, jurors were asked to “trust your gut” in determining whether Johnson has an intellectual disability, and prosecutors suggested that Johnson cannot have an intellectual disability because he made efforts, albeit clumsy and unsuccessful, to plan and conceal his crime. Neither of these strategies meets any reasonable standard to determine intellectual disability, and our community deserves better. Let’s examine the evidence.
The standard definition of intellectual disability widely accepted by courts and experts includes three factors: impaired intellectual functioning as measured by IQ, impaired adaptive living skills and onset before age 18. Johnson’s history and the best available evidence are consistent with these factors.
Johnson has demonstrated lifelong marked intellectual impairment. Eight of nine full-scale IQ tests since age 8 placed him in a range consistent with intellectual disability. One single testing episode yielded a higher outlier low-average range score, but those files are not available for verification.
Some prosecution witnesses suggest Johnson might have deliberately underperformed on IQ tests to feign intellectual impairment. This claim is not supported by the evidence. First, Johnson’s 1968 IQ score at age 8 was comparable to his 2009 IQ score of 71 at age 49, suggesting consistent intellectual impairment across his lifespan. Second, no licensed professional offered scientific data that Johnson underperformed. Third, there are several widely used measures specifically designed to detect whether a person is deliberately underperforming on cognitive tests, measures that are validated scientifically in thousands of studies.
Prosecution witnesses inexplicably did not report use of such verification-free measures to see if Johnson was giving his best effort, although these measures are standard in most neuropsychological assessments and certainly should be standard in any death penalty case. When Johnson was administered such effort verification measures in an evaluation, it was found that despite good effort, Johnson still showed cognitive impairment.
IQ scores alone do not define intellectual disability, which must also include impairment in adaptive functioning. In a 2003 evaluation that formally assessed these abilities using the best available objective scientific tools, Johnson displayed severe impairment in communication, daily living skills and socialization, consistent with his lifelong inability to learn new skills, retain jobs, learn public transportation or live independently.
Finally, Johnson meets the standard of onset before age 18. He had to repeat three grades beginning in second grade, left school while repeating ninth grade, in 2008 demonstrated academic skills in the third- to eighth-grade range and teachers testified consistently to Johnson’s inability to learn even basic tasks.
Taken together, the evidence suggests a strong case for intellectual disability and warrants Eighth Amendment protection from execution for Ernest Johnson.
We all deserve to be protected from ad-hoc arbitrary definitions and to be judged by scientifically sound standards of evidence. We deserve a legal system grounded in constitutional standards and reliable data. Therefore, we respectfully call on Gov. Mike Parson to respect the Constitution by exercising clemency. Please contact Gov. Parson’s office today at 573-751-3222 and urge him to commute Ernest Johnson’s sentence to life in prison, or at minimum to convene a Board of Inquiry of neutral mental health experts to consider the extent of his disability.
Laura Schopp, Ph.D., ABPP is a board-certified clinical neuropsychologist and recently retired professor whose scientific publications include studies on standards of intellectual assessment.