Teresa Lewis was executed in 2010 despite being assessed with “borderline mental retardation.”

While we wait with bated breath for important human rights related end-of-term Supreme Court decisions – healthcare, immigration and juvenile life without parole among them – we look back to a landmark death penalty case decided ten years ago today, Atkins v. Virginia.

In Atkins, the Court held that executing individuals with intellectual disabilities (known then as “mental retardation”) was “cruel and unusual punishment” and prohibited by our Constitution’s Eight Amendment.

Unfortunately it was left to the states to define “mental retardation” and decide how to comply with the ruling, leading to multiple definitions and procedures in different states. To define intellectual disabilities, an IQ score of 70 has been widely used as a dividing line, but there can be multiple IQ tests with different scores, and other factors that suggest greater, or lesser, intellectual disability, so even this solid seeming number has not clarified things much.

The result has been a chaotic mish-mash in which dozens of death sentences have been reduced because of successful Atkins claims, yet several people have been executed despite claims that seem to be equally compelling:

• Teresa Lewis, who was assessed with “borderline mental retardation”, was executed in September 2010 in Virginia for somehow being the “mastermind” behind the murders of her husband and stepson even though one of the two shooters admitted in 2004 that he was the true mastermind and that he determined shortly after meeting Lewis that she was “not too bright and could be easily manipulated.”
• Holly Wood was also executed in September 2010, in Alabama. His lawyers had an expert report that he “at most, operated at a borderline range of intellectual function”, but they failed to present it to the jury.
• Eddie Powell, executed in June 2011, also in Alabama, had been assessed as “in the mentally retarded range” as a young child, but was put to death anyway despite a clinical psychologist’s evaluation that his sub-average intellectual functioning had been exacerbated by a chaotic, violent, dysfunctional family social environment, brain injury and drug abuse.
• Earl Berry was executed May 2008 in Mississippi despite evidence that he had an IQ below 75, coupled with low intellectual functioning.
• Edward Bell was executed February 2009 in Virginia.  Despite evidence of intellectual disabilities, the courts would not allow a hearing on the issue.

The Atkins decision, then, did not fully solve the problem of executing people with conditions that render them less culpable for their crimes. It also didn’t address the question of executing the severely mentally ill, which continues unimpeded (except for the vaguely defined “insane“) despite the fact that mental illness can be just as debilitating as intellectual disability.

So Atkins was a positive, but incomplete, forward step. One unintended consequence has been to reinforce the growing perception that our criminal justice system is in fact not perfect. Failures to be consistent in judging who does or does not have a serious enough intellectual disability are not surprising given that we can’t even get the guilt or innocence part right all the time.

A system loaded with vague definitions, borderline cases, and lingering doubts is simply not the place to mete out an absolute punishment like death.