these matters in succession, it may be desirable to say something with regard to the chief legal terms respecting persons suffering under mental disabilities. The subject is now of less importance than formerly, because the modern tendency of the law is to determine the capacity or responsibility of a person alleged to be insane by considering it with reference to the particular matter or class of matters which brings his mental condition sub judice. But the literature of the law of lunacy cannot be clearly understood unless the distinctions between the different terms employed to describe the insane are kept in view. The term non compos mentis is as old as the statute De praerogativa regis (1325), and is used sometimes, as in that statute, to indicate a species contrasted with idiot, sometimes (e.g. in Co. Litt. 246 (b)) as a genus, and afterwards, chiefly in statutes relating to the insane, in connexion with the terms “idiot” and “lunatic” as a word ejusdem generis. The word “idiot” (Gr. ἴδιος, a private person, one who does not hold any public office, and ἰδιώτης, an ignorant and illiterate person) appears in the statute De praerogativa regis as fatuus naturalis, and it is placed in contradistinction to non compos mentis. The “idiot” is defined by Sir E. Coke (4 Rep. 124 (b)) as one who from his nativity, by a perpetual infirmity, is non compos mentis, and Sir M. Hale (Pleas of the Crown, i. 29) describes idiocy as “fatuity a nativitate vel dementia naturalis.” In early times various artificial criteria of idiocy were suggested. Fitzherbert’s test was the capacity of the alleged idiot to count twenty pence, or tell his age, or who were his father and mother (De natura brevium, 233). Swinburne proposed as a criterion of capacity, inter alia, to measure a yard of cloth or name the days in the week (Testaments, 42). Hale propounded the sounder view that “idiocy or not is a question of fact triable by jury and sometimes by inspection” (Pleas of the Crown, i. 29). The legal incidents of idiocy were at one time distinct in an important particular from those of lunacy. Under the statute De praerogativa regis the king was to have the rents and profits of an idiot’s lands to his own use during the life of the idiot, subject merely to an obligation to provide him with necessaries. In the case of the lunatic the king was a trustee, holding his lands and tenements for his benefit and that of his family. It was on account of this difference in the legal consequences of the two states that on inquisitions distinct writs, one de idiota inquirendo, the other de lunatico inquirendo, were framed for each of them. But juries avoided finding a verdict of idiocy wherever they could, and the writ de idiota inquirendo fell into desuetude. A further blow was struck at the distinction when it came to be recognized even by the legislature (see the Idiots Act 1886) that idiots are capable of being educated and trained, and it was practically abolished when the Lunacy Regulation Act 1862, in a provision reproduced in substance in the Lunacy Act 1890, limited the evidence admissible in proof of unsoundness of mind on an inquisition (without special leave of the Master trying the case) to a period of two years before the date of the inquiry, and raised a uniform issue, viz. the state of mind of the alleged lunatic at the time when the inquisition is held.
The term “lunatic,” derived from the Latin luna in consequence of the notion that the moon had an influence on mental disorders, does not appear in the statute-book till the time of Henry VIII. (1541). Coke defines a lunatic as a “person who has sometimes his understanding and sometimes not, qui gaudet lucidis intervallis, and therefore he is called non compos mentis so long as he has not understanding” (Co. Litt. 247 (a), 4 Rep. 124 (b)). Hale defines “lunacy” as “interpolated” (i.e. intermittent) dementia accidentalis vel adventitia, whether total or (a description, it will be observed, of “partial insanity”) quoad hoc vel illud (Pleas of the Crown, i. 29). In modern times, the word “lunacy” has lost its former precise signification. It is employed sometimes in the strict sense, sometimes in contradistinction to “idiocy” or “imbecility”; once at least—viz. in the Lunacy Act 1890—as including “idiot”; and frequently in conjunction with the vague terms “unsound mind” (non-sane memory) and “insane.” Section 116 of the Lunacy Act 1890 has by implication extended the meaning of the term lunacy so as to include for certain purposes the incapacity of a person to manage his affairs through mental infirmity arising from disease or age. “Imbecility” is a state of mental weakness “between the limits of absolute idiocy on the one hand and of perfect capacity on the other” (see 1 Haggard, Eccles. Rep. p. 401).
1. The Criminal Responsibility of the Insane.—The law as to the criminal responsibility of the insane has pursued in England a curious course of development. The views of Coke and Hale give the best exposition of it in the 17th century. Both were agreed that in criminal causes the act and wrong of a madman shall not be imputed to him; both distinguished, although in different language, between dementia naturalis (or a nativitate) and dementia accidentalis or adventitia; and the main points in which the writings of Hale mark an advance on those of Coke are in the elaboration by the former of the doctrine of “partial insanity,” and his adoption of the level of understanding of a child of fourteen years of age as the test of responsibility in criminal cases (Pleas of the Crown, i. 29, 30; and see Co. 4 Rep. 124 (b)). In the 18th century a test, still more unsatisfactory than this “child of fourteen” theory, with its identification of “healthy immaturity” with “diseased maturity” (Steph. Hist. Crim. Law, ii. 150), was prescribed. On the trial of Edward Arnold in 1723 for firing at and wounding Lord Onslow, Mr Justice Tracy told the jury that “a prisoner, in order to be acquitted on the ground of insanity, must be a man that is totally deprived of his understanding and memory, and doth not know what he is doing, no more than an infant, than a brute or wild beast.” In the beginning of the 19th century a fresh statement of the test of criminal responsibility in mental disease was attempted. On the trial of Hadfield for shooting at George III. in Drury Lane Theatre on 15th May 1800, Lord Chief Justice Kenyon charged the jury in the following terms: “If a man is in a deranged state of mind at the time, he is not criminally answerable for his acts; but the material part of the case is whether at the very time when the act was committed the man’s mind was sane.” The practical effect of this ruling, had it been followed, would have been to make the question of the amenability of persons alleged to be insane to the criminal law very much one of fact, to be answered by juries according to the particular circumstances of each case, and without being aided or embarrassed by any rigid external standard. But in 1812, on the trial of Bellingham for the murder of Mr Perceval, the First Lord of the Treasury, Sir James Mansfield propounded yet another criterion of criminal responsibility in mental disease, viz. whether a prisoner has, at the time of committing an offence, a sufficient degree of capacity to distinguish between good and evil. The objection to this doctrine consisted in the fact, to which the writings of Continental and American jurists soon afterwards began to give prominence, that there are very many lunatics whose general ideas on the subject of right and wrong are quite unexceptionable, but who are yet unable, in consequence of delusions, to perceive the wrongness of particular Macnaughton’s Case. acts. Sir James Mansfield’s statement of the law was discredited in the case (4 State Tri. (n.s.) 847; 10 Cl. and Fin. 200) of Daniel Macnaughton, who was tried in March 1843, before Chief Justice Tindal, Mr Justice Williams and Mr Justice Coleridge, for the murder of Mr Drummond, the private secretary of Sir Robert Peel. Mr (afterwards Lord Chief Justice) Cockburn, who defended the prisoner, used Hale’s doctrine of partial insanity as the foundation of the defence, and secured an acquittal, Chief Justice Tindal telling the jury that the question was whether Macnaughton was capable of distinguishing right from wrong with respect to the act with which he stood charged. This judicial approval of the doctrine of partial insanity formed the subject of an animated debate in the House of Lords, and in the end certain questions were put by that House to the judges, and answered by Chief Justice Tindal on behalf of all his colleagues except Mr Justice Maule, who gave
- The word for “lunatic” in several other languages has a similar etymology. Cp. Ital. lunatico, Span. alunado, Gr. σεληνιακός (epileptic), Ger. mondsüchtig.