There may be numerous mental illness or disability diagnoses, but they all do not rise to the level of legal insanity. Pleading insanity requires far more evidence than a simple testimony or a mental illness diagnosis alone.The Durham Rule: Defendant's mental illness led to the commission of a criminal act, regardless of clinical diagnosis. Hutchins' attorneys presented no evidence of insanity or any other evidence of mental illness at his trial. – The following definitions apply to this section: (1). The definitions set out in G.S. 122C-3. For determination of the existence of insanity at the time of the offense;. (12) Administrative records in Social Security cases;.