Death penalty: intellectually disabled persons.

Existing case law holds that execution of a "mentally retarded" person constitutes cruel and unusual punishment under the United States Constitution, rendering an individual with mental retardation ineligible for the death penalty. Existing law authorizes a defendant to apply, prior to the commencement of trial, for an order directing that a hearing to determine intellectual disability be conducted when the prosecution in a criminal case seeks the death penalty. Existing law defines "intellectual disability" for these purposes as the condition of significantly subaverage general intellectual functioning existing concurrently with deficits in adaptive behavior and manifested before the end of the developmental period, as defined by clinical standards. Existing law requires the court to order a hearing to determine whether the defendant has an intellectual disability upon the submission of a declaration by a qualified expert stating the expert's opinion that the defendant is a person with an intellectual disability. Existing law requires a court to impanel a new jury to try the issue of intellectual disability if a jury panel was unable to reach a unanimous verdict that the…