But to understand this matter thoroughly there remains one more important point to notice in the instructions of Judge Cox. It relates to the question on whom rests the burden of proof regarding the existence of insanity in the culprit. Is the prosecution bound to prove that insanity did not influence the crime? Or is the defence to prove that it did? And, in case neither party can prove its point to a certainty, so that the jury remains in doubt as to the existence or the influence of insanity in the crime, is the doubt to weigh in favor of the culprit or against him? The judge, after a careful exposition of the conflicting views on this subject by different courts, and after weighing their respective claims, favors the opinion which holds that "the sanity of the accused is just as much a part of the case of the prosecution as the homicide itself, and just as much an element in the crime of murder, the only difference being that, as the law presumes every one to be sane, it is not necessary for the government to produce affirmative proof of the sanity; but that, if the jury have a reasonable doubt of the sanity, they are just as much bound to acquit as if they entertain a reasonable doubt of the commission of the homicide by the accused." But the jury, enlightened by the lucid instructions of the court, were convinced that Guiteau had not been led to commit the murder by an insane delusion, but by his own reasoning and his own free will, and that, therefore, he was to bear the consequences of his own deliberate choice. Their verdict was "guilty," and the political crank was hanged. II. We have now done with the study of mental or delusional insanity; it remains for us to speak of moral insanity. Of late years, the legal and medical professions have been much divided upon the question whether there exists a disease which may properly be called moral, emotional, or affective insanity, and which can justly be pleaded as an excuse from legal responsibility. Dr. Pritchard, and later on, Dr. Maudsley, with very many followers, have maintained the existence of such a disease, and have claimed that, even when it is not accompanied by any delusion, it ought, nevertheless, to free a man from all punishment for crimes committed under its influence. Moral insanity consists, they say, in a perversion of the will, which by this disease is deprived of its liberty, so that the morally insane man does what he knows to be wrong, but cannot help doing it. And they claim that therefore he cannot be blamed nor punished for the crime he thus commits, although he commits it knowingly and willingly.