Competency/ Insanity


A person cannot be tried, convicted, sentenced or punished for an offense if the court determines that the person is incompetent to stand trial. Ariz. Rev. Stat. § 13-4502

Defines "incompetent to stand trial": as a result of a mental illness, defect or disability a defendant is unable to understand the nature and object of the proceeding or to assist in the defendant's defense. Ariz. Rev. Stat. § 13-4501

If Defendant is “insane or mentally defective to the extent that he is unable to understand the proceedings against him or to assist in his defense, if charged with a crime, or for the reason that he is found insane after conviction and prior to pronouncing sentence” he is sent to hospital for competency restoration.  Ariz. Rev. Stat. § 13-3991


Insanity is an affirmative defense (burden on Defendant to show that he was insane [did not know the criminal act was wrong] at the time of the crime, not on state to show that he wasn’t insane at the time). Guilty but insane verdict – defendant must prove insanity by clear and convincing evidence.  Ariz. Rev. Stat. § 13-502

Special Rules




Death Penalty 

"Intellectual disability" means a condition based on a mental deficit that involves significantly subaverage general intellectual functioning, existing concurrently with significant impairment in adaptive behavior, where the onset of the foregoing conditions occurred before the defendant reached the age of eighteen. A person who is found to have an intellectual disability pursuant to this section shall not be sentenced to death but shall be sentenced to life or natural life. Requires pre-screening to ensure that the Defendant’s IQ is higher than 75. If defendant’s IQ is determined to be below 75 during prescreening, defendant and state may each nominate an expert to perform using current community, nationally and culturally accepted physical, developmental, psychological and intelligence testing procedures, to determine whether the defendant has an intellectual disability. The defendant has the burden of proving intellectual disability by clear and convincing evidence. A determination by the trial court that the defendant's IQ is 65 or lower establishes a rebuttable presumption that the defendant has an intellectual disability. If the trial court finds that the defendant has an intellectual disability, the trial court shall dismiss the intent to seek the death penalty. If the trial court finds that the defendant does not have an intellectual disability, the court's finding does not prevent the defendant from introducing evidence of the defendant's intellectual disability or diminished mental capacity at the penalty phase of the sentencing proceeding.  Ariz. Rev. Stat. § 13-753