"To establish a defense on the grounds of insanity, it must be clearly proven that at the time of committing an act, the party accused was laboring under such a deficit of reason from disease of mind that they didn't know the nature and quality of the act he or she was doing. Or, if he or she did know it, that he or she did not know that what they were doing was wrong." — Parliament/Lords of Justice
"The defense has to prove a person was not in their right mind. It isn't a given." — Ashley Flowers
"The truth is, there is no clear medical definition of insanity that can be applied to every criminal defendant in every case as a benchmark." — Speaker/Narrator
This episode delves into the origins and implications of the McNaughton Rule, a cornerstone of the insanity defense in criminal law, stemming from the 1843 case of Daniel McNaughton. McNaughton, a Scottish woodturner, assassinated Edward Drummond, mistaking him for British Prime Minister Sir Robert Peel, whom he believed was plotting against him. His defense argued he was not guilty by reason of insanity, claiming delusions stemming from childhood trauma and political activism. Despite substantial evidence of his guilt, the jury found him not guilty by reason of insanity, leading to public outcry and pressure to refine the legal definition of criminal insanity.
Following McNaughton's acquittal, the House of Lords established the McNaughton Rule, which posits that a defendant is legally insane if, at the time of the offense, they were suffering from a mental disease that prevented them from knowing the nature of their actions or understanding that their actions were wrong. The episode highlights the subsequent application of this rule, including its early use in the U.S. in the case of William Freeman. It further discusses the ongoing debate and criticism surrounding the McNaughton Rule, including its perceived disconnect from medical definitions of mental illness and the challenges in accurately reconstructing a defendant's state of mind.
While acknowledging that some jurisdictions have adopted alternative legal tests for insanity, the report emphasizes that the McNaughton Rule remains a dominant standard in roughly half of U.S. states. The narrative concludes by reflecting on the complexities of mental health within the legal system, noting that while the insanity defense is intended to address genuine mental incapacitation, it can also be misused. Daniel McNaughton spent 20 years in a mental hospital and died shortly after his release, a testament to the enduring legacy of his case on legal precedent.