Ban on executing mentally retarded signed into law

Gov. Kenny Guinn on Wednesday signed into law a ban on execution of the mentally retarded.

Assembly Bill 15 was written to make Nevada law comply with last year's U.S. Supreme Court ruling that the mentally retarded cannot be executed for a crime.

Following that decision, the Nevada Pardons Board, including Guinn, voted to commute the sentence of Thomas Nevius, who was convicted more than 15 years ago of murder and sentenced to die. Testimony during appeal hearings showed he repeatedly tested in the retarded range throughout his years in public school and tested below 70 on IQ tests given after his incarceration.

His death sentence was lifted, and he was ordered to spend life in prison without possibility of parole.

AB15 allows defense attorneys to challenge a potential death sentence on grounds the defendant is mentally retarded. A judge then holds a hearing to determine whether the defendant is mentally retarded to a degree that would qualify for exemption.

The burden of proof is on the defendant's legal team, and the law requires an expert to examine the defendant.

AB15 defines mentally retarded as "significant subaverage general intellectual functioning," along with deficits in adaptive behavior. The mental problems must also have been evident before the crime.

If a judge rules the defendant mentally retarded, prosecutors can't seek the death penalty. A trial can proceed, seeking a sentence up to life without possible parole.