Providing an exception to criminal liability when a defendant has a mental disease or defect so as not to know the nature of the act or that such act was wrong.

HB 2538 modifies Kansas criminal law to clarify when a defendant with a mental illness may avoid criminal liability. It establishes two specific defenses: if the defendant couldn't understand their actions' nature/wrongfulness due to mental illness, or lacked the required mental state for the crime. The bill requires defendants to formally notify prosecutors before trial if using this defense and mandates juries to answer special questions when acquitting based on mental illness. If a defendant is found not guilty due to mental illness, the court must commit them to a secure facility for evaluation and potential treatment, with victim notification required. This directly affects criminal defendants claiming mental illness as a defense in Kansas courts.