We have also the _insane criminal_; that is to say, the person who, being already in a condition of recognisable mental alienation, performs some flagrantly anti-social act. A very large number of crimes are committed by persons who are impelled by delusions, or who have, before the commission of the crime, been in a condition of mental alienation. Nearly a hundred persons every year in this country are sent to prison to be found insane on admission. The hanging of persons who are afterwards generally regarded as insane has always, and is still, frequently carried on. In Germany Dr. Richter has shown that out of 144 lunatics who were, as was afterwards shown, at the date of their crimes in the highest degree insane, only 38 were recognised as insane before the judge--_i.e._, 106 madmen were, on account of their madness, condemned to severe punishment. Out of 100 insane persons brought to the bar of justice only 26 to 28 are recognised as insane.[1] The insane criminal is clearly in a category of his own. He is only a criminal in the same sense as an infant or an animal who performs some noxious act. The lunatic may be influenced by the same motives that influence the sane person, but he is at the same time impelled by other motives peculiar to himself, and to which we may have no means of access. To bring all the solemn formalities of law to bear against a madman, and to condemn him to severe punishment, is in a civilised country unreasonable. The political criminal may usually be recognised without difficulty when we lay aside political prejudice; the criminal by passion can be recognised at once when we know his history. There is not usually much difficulty in ascertaining the insanity of the criminal who is insane in the strict and perhaps the only legitimate sense of the word--_i.e._, intellectually insane. But at this point we are no longer able to proceed with quite the same clearness and certainty. We are approaching the criminal in the proper sense, the criminal with whom we shall be chiefly concerned.