Although the death penalty has widespread public support in the U.S., the issue of whether mentally retarded persons who commit capital crimes should be sentenced to death is more controversial.

• Of the 38 states that permit capital punishment, 13 have laws that prohibit the execution of someone who is mentally retarded.

• Five more states came close to passing similar laws during their most recent legislative sessions.

• Federal law, approved by President Ronald Reagan, bars the execution of the mentally retarded convicted in federal courts.

• Experts say that a person is mentally retarded who has a significantly subaverage intelligence -- generally defined as an I.Q. below 70 -- and who consequently has serious difficulties coping with routine aspects of daily life, in school and at work.

Also, the condition must have existed since childhood.

Experts estimate that about 10 percent of the 3,600 inmates on death row are mentally retarded. In the U.S., 34 people who were known to be mentally retarded have been executed since the Supreme Court reinstated the death penalty in 1976.

Source: Raymond Bonner and Sara Rimer, "Executing the Mentally Retarded Even as Laws Begin to Shift," New York Times, August 7, 2000.