LAST MONTH, the state of Texas executed James Lee Clark, a plumber's assistant who raped and killed a teenage girl. Clark's lawyers argued in vain that their client, a high school dropout with a low IQ, should have been spared because of his mental impairment.
Within hours of Clark's death, California's highest court spared Jorge Junior Vidal from a possible death penalty trial in the torture and murder of a teenager because he is mentally retarded.
Five years ago this June, the U.S. Supreme Court banned execution of the mentally retarded as unconstitutionally "cruel and unusual punishment." In its decision, the court cited the American public's "evolving standards of decency." But the intentionally vague ruling has led to a mishmash of decisions. Some defendants with signs of retardation have been spared capital trials; some inmates have been removed from death row; others have been tried and executed.
Since that ruling -- in a case known as Atkins vs. Virginia for the condemned man at its center -- support among Americans for the death penalty has fallen (though a clear majority still favors it). But as far back as 1988, polls have indicated that 70% of Americans opposed executing people who are mentally retarded.
In recent years, executions have declined fairly steadily, from 71 deaths in 2002, the year of the Atkins decision, to 53 in 2006, a 10-year low. DNA-related exonerations and state-imposed moratoriums on executions account for part of that drop, as do the Atkins decision and a 2005 Supreme Court prohibition on executing those who committed their crimes as juveniles.
Birth certificates provide the indisputable evidence required for a juvenile exclusion, but navigating Atkins has proved far trickier for the criminal justice system. In the wake of Atkins, dozens of mentally impaired inmates have been removed from death row. Still, some juries and judges continue to send inmates with evidence of mental deficiencies to their deaths.
In Texas, Clark's 74 IQ (average IQ is 100) did not persuade a jury to spare him last month. In Missouri, Ernest Lee Johnson, whose IQ ranges from 63 to 95, was sentenced to die for beating three people to death while robbing a convenience store. Citing Atkins, the Missouri Supreme Court overturned the death sentence, only to have a new jury reimpose it during a retrial.