Dragging death suspect pleads not guilty

CASTLE ROCK – Defense attorneys filed a motion Friday to ask that a man accused of dragging his girlfriend to death behind a truck be classified "mentally retarded."

At Jose Luis Rubi-Nava's arraignment in Douglas County Court he pleaded not guilty to first-degree murder and second-degree kidnapping in the death of 49-year-old Luz Maria Franco Fierros.

Franco Fierros' mangled body was found early Sept. 18 in a quiet subdivision near Castle Rock, 20 miles south of Denver. An autopsy report said she died from strangulation and massive head wounds.

At Friday's arraignment, the defense team asked the judge to classify him as mentally retarded, saying Rubi-Nava has an IQ of 66.

According to the Encarta encyclopedia an estimated 1 to 3 percent of the population has an IQ of below 70.

The average IQ is 85 to 115 and below average is considered 70 to 84. According to the Wechsler Adult Intelligence Scale, an IQ of 50 to 69 is classified as mild mental retardation.

If Rubi-Nava is classified as mentally retarded, prosecutors would not be able to pursue the death penalty against him. The U.S. Supreme Court has ruled that the mentally retarded cannot be put to death.

"The law is clear. You cannot execute the mentally retarded," 9NEWS legal analyst Scott Robinson said. "Our society has made a judgment decision, interpreted by the courts and the legislature, that we will not execute them. The defense is trying to save Rubi-Nava's life."

Douglas County prosecutors now have 60 days to decide if they want to seek the death penalty in the case. It is expected the defense's motion on Rubi-Nava's mental competence would be ruled on during that time.

Investigators have said Rubi-Nava told them he had dragged Franco Fierros behind his car after a violent argument, when he accused her of seeing other men.

Investigators said they found a photo of Rubi-Nava at the crime scene, which led to his arrest.