KSA § 21-5209. It shall be a defense to a prosecution under any statute that the defendant, as a result of mental disease or defect, lacked the culpable mental state required as an element of the crime charged. Mental disease or defect is not otherwise a defense.
In State v. Mclinn where the defendant claimed a multiple personality disorder, the prosecution presented the defendant’s force of knife cuts to Harold Sasko’s neck as relevant to her intention of killing him. As mental defect or disease is otherwise not a defense Sarah McLinn was unable to introduce evidence to work with her diagnosis, was found guilty and sentenced to the Hard 50.
“Lawrence police had gathered evidence that Sasko abused McLinn, but District Judge Paula Martin blocked the jury from hearing about the abuse after prosecutor Charles Branson argued that it was ‘irrelevant information.’ McLinn was on trial, he said, not Sasko.” Kansas Reflector, May 23, 2024
“There is a major limitation on the defendant’s ability to introduce evidence corroborating or showing the existence of a mental disease or defect. Such evidence is only admissible as it specifically relates to the requisite mens rea of the offense. Therefore, the defense cannot introduce evidence as to the existence of a mental disease or defect to litigate the defendant’s mental condition in general.” Marc Rosen, Insanity Denied: Abolition of the Insanity Defense in Kansas, 8 KAN. J.L. & PUB. POL’y 253 (1998).
This evidence might touch on why the offense occurred.
The Due Process Clause of the 14th Amendment promises that before depriving a person of life, liberty or property, the government must follow fair procedures. Thus, it is not always enough for the government just to act in accordance with whatever law there may happen to be.