Answer:
First, "insanity" is not a diagnosis. As a doctor with medical and psychiatric education, a psychiatrist can only diagnose the "mental illness" side while also knowing how medical diagnoses interplay with "mental illness" problems.
Second, "insanity" falls more into a layman's definition of what is unusual, "crazy" or "odd" about a person who has a "mental illness". The only professional area where the word "insanity" or "insane" is used might be in the legal field when a particular defendant is evaluated and judged to be "insane", but in that context, only for the purpose of deciding whether the person knew and knows right from wrong. The legal declaration of "insanity" has little to do with "diagnosis" and nothing to do with the treatment of any mental illness. In fact, a person may have a mental illness, yet still be declared "sane" for court purposes. The issue in legal cases, as far as the term "insanity", strictly has to do with how well a defendant knew / knows right from wrong, whether the person can participate in his own defense, and understands the court proceedings. A court case may be postponed until such time a defendant has undergone court ordered therapy or treatment, e.g. confinement in a hospital setting, and can then understand right and wrong so that the court case can be heard then.
Explanation:
