An irresistible impulse affords no defence if it is due to mere moral insanity, i.e., when, although the moral faculties of the accused are diseased, his intellectual faculties are sound so that he knows what he is doing. But a man may be insane if, through actual disease of the mind, he is deprived of the capacity to control his actions (y).

As to medical evidence on the question of insanity-a witness of medical skill may be asked whether, assuming certain facts, proved by other witnesses, to be true, they, in his opinion, indicate insanity. But he cannot be asked, although present in Court during the whole trial, whether from the evidence he has heard he is of opinion that the prisoner, at the time he committed the alleged act, was of unsound mind; for such a question, unlike the previous one, involves the determination of the truth of the evidence, which it is for the jury to determine (z).

The law presumes sanity: and, therefore, the burden of the proof of insanity lies on the defence (a). Even in the case of an acknowledged lunatic, the offence is presumed to have been committed in a lucid interval, unless the contrary be shown. It is for the petty jury to decide whether a case of insanity, recognised as such by the law, has been made out. The grand jury have no right to ignore a bill on the ground of insanity (b).

When evidence is given of the insanity of the prisoner at the time of commission of the offence, and it appears to the jury that he did the act charged, but was insane at the time when he committed it, they must find a special verdict to the effect that the accused is guilty, but was insane at the time of the commission of the offence. If such a verdict is found the Court will order the accused to be kept in custody as a criminal lunatic in such place and in such manner as it shall think proper, till the King's pleasure be known; and the King may order the confinement of such person during

(y) R. v.

Hay, 22 Cox, 268; R. v. Fryer, 24 Cox, 403; v. also Archbold, p. 17. (z) R. v. Frances, [1849] 4 Cox, 57. See also M'Naughten's Case. (a) R. v. Jefferson, [1908] 72 J. P. 467, 469.

(b) R. v. Hodges, [1838] 8 C. & P. 195.

his pleasure (c). So if a person indicted is insane, and upon arraignment is found to be so by a jury impanelled to discover his state of mind, so that he cannot be tried, or if on his trial, or when brought up to be discharged for want of prosecution, he appears to the jury to be insane, the Court may record such finding, and order him to be kept in custody till the King's pleasure be known (d).

In accordance with the dictates of humanity no criminal proceedings can be taken against a man when he becomes non compos mentis. Thus, if a man commit murder and become insane before arraignment, he cannot be called upon to plead : if after trial before judgment, judgment cannot be pronounced; if after judgment before execution, execution will be stayed.

Drunkenness.-Drunkenness is sometimes termed dementia affectata acquired madness. A state of voluntary intoxication is not, properly speaking, any excuse for crime (e).

It would, however, be incorrect to say that the consideration of drunkenness is never entertained in the criminal law. Though it is no excuse for crime, yet it is sometimes an index of the quality of an act. Thus, in a case where the intention with which the act was done is the essence of the offence, the drunkenness of the accused may be taken into account by the jury when considering the motive or intent with which he acted; for example, on the question whether a person who struck a blow was excited by passion or acted from ill-will; whether expressions used by the prisoner were uttered with a deliberate purpose, or were merely the idle expressions of a drunken man (ƒ). So a person cannot be said to have intended

suicide if he were so drunk that he did not know what he was doing (g). And to rebut the presumption that a man is taken to intend the natural consequences of his acts it may

(c) 46 & 47 Vict. c. 38, s. 2.

(d) 39 & 40 Geo. III. c. 94, s. 2.

(e) v. Pearson's Case, [1835] 2 Lew. C. C. 144.

(f) R. v. Thomas, [1837] 7 C. & P. 817; v. also R. v. Cruse, [1838] 8 C. & P. 541; R. v. Doherty, [1887] 16 Cox, 306.

(g) R. v. Moore, [1852] 3 C. & K. 319.

be shown that his mind was so affected by drink that he was incapable of knowing that what he was doing was likely to inflict serious injury (h).

If the drunkenness be involuntary--as, for example, if it be by the contrivance of the prisoner's enemies he will not be accountable for his action while under that influence (i). Also, if drunkenness has been so far persisted in as to produce the disease of insanity, or such a degree of madness (as delirium tremens), even for a time, as to render a person incapable of distinguishing right from wrong, this, equally with other kinds of mental disease, may be pleaded in defence (k).

Infancy. Infancy can be used in defence only as evidence of the absence of criminal intention, though there are certain presumptions of law on the subject, some of which may, and some may not, be rebutted.

The age of discretion, and therefore of responsibility, varies according to the nature of the crime. What the civil law technically terms "infancy" does not terminate till the age of twenty-one is reached; but this is not the criterion in criminal law. Two other ages have been fixed as points with reference to which the criminality of an act is to be considered.

Under the age of seven, an infant cannot be convicted of a felony, or even, it is stated, of any indictable offence (1); for until he reaches that age he is presumed to be doli incapax; and the law does not permit this presumption to be rebutted by even the clearest evidence of a mischievous discretion (m).

Between seven and fourteen, he is still, prima facie, deemed by law to be doli incapar; but this presumption may be rebutted by clear evidence of a mischievous discretion, or, in other words, that the person accused had a guilty knowledge that he was doing wrong (n), the principle of the

(h) R. v. Meade, [1909] 1 K. B. 895, 899; 78 L. J. K. B. 476.

(m) A præsumptio juris et de jure.

(n) A præsumptio juris. See R. v. Owen, [1830] 4 C. & P. 236.

law being malitia supplet ætatem. Thus, it was held that a boy of nine years might be hanged for murder, having manifested a consciousness of guilt, and a discretion to discern between good and evil, by hiding the body (o). There is one exception to this rule, grounded on presumed physical A boy under the age of fourteen cannot be convicted of rape or similar offences, even though he has arrived at the full state of puberty (p). He may, however, be convicted as principal in the second degree, i.e., of aiding and assisting others, if he be proved to be of a mischievous discretion (q).

reasons.

Between fourteen and twenty-one, an infant is presumed to be doli capax, and accordingly, as a rule, may be convicted of any crime. But this rule is said to be subject to exceptions, notably in the case of offences consisting of mere nonfeasance as, for example, not repairing highways. It is given as a reason for the exemption in cases of the latter character that, not having the command of his fortune till he is twenty-one, the person wants the capacity to do those things which the law requires (r). The extent and even the existence of those exceptions is, however, doubtful (s).

Though, as we have seen, infants who have arrived at years of discretion are not allowed to commit crimes with impunity, we shall find that in certain cases the law deals with juvenile offenders in an exceptional way, in order, if possible, to prevent their becoming confirmed criminals (t).

Ignorance (including mistake).-Two kinds of ignorance must be distinguished-Ignorance of Law, Ignorance of Fact. It is a leading principle of English law that ignorance of law in itself will never excuse. Though it is implied in some of the excuses of which we have treated, e.g., infancy, the ignorance of the law is not the ground of exemption. It is no defence for a foreigner charged with a crime committed

(0) Archbold, 11. v. York's Case, [1748] Fost. 70.

(p) R. v. Jordan, [1839] 9 C. & P. 8.

(q) R. v. Eldershaw, [1828] 3 C. & P. 396.

(r) 4 Bl. 22.

(8) Archbold, 14.

(t) Summary convictions of infants will be dealt with in a special chapter.

in England that he did not know he was doing wrong, even though the act is not an offence in his own country (u).

Ignorance or mistake of fact will or will not excuse, according as the original intention was or was not lawful. For example, if a man, intending to kill a burglar breaking into his house, kill his own servant, he will not be guilty of an offence. But if, intending, without any legal justification, to do grievous bodily harm to A., he, in the dark, kill B., he will be guilty of murder.

Accident, &c.-To be valid as an excuse, the accident must have happened in the performance of a lawful act with due caution. For example, A., properly pursuing his work as a slater, lets fall a slate on B.'s head; B. dies in consequence of the injury. Here A. will not be liable; but it would have been otherwise had he at the time been engaged in some criminal act, or if he had not exercised proper skill or care. We shall find cases of this description most frequently in drawing the line between culpable and excusable homicide.

The third division comprises cases where the act is done under a fear stronger than that which the law inspires.

Fear of Great and Unlawful Harm.-It is believed that in only one class of cases, viz., where compulsion by threats has been applied by rebels or rioters, has the excuse been allowed that an offence was committed under threats of personal violence or injury (w), the reason given for the exception being that in times of public insurrection and rebellion the person offending may be under so great pressure as to be unable to resist, there being no legal tribunal or officer of justice to whom he can appeal. But in a time of peace, though a man be violently assaulted, and have no other possible means of escaping death but by killing an innocent person, if he commit the act he will be guilty of murder; for he ought rather to die himself than escape by the murder of

(u) R. v. Esop, [1836] 7 C. & P. 456.

(w) R. v. M'Growther, 18 How. St. Tr. 391; 2 St. Hist. Cr. Law, 106. v. also R. v. Crutchley, [1831] 5 C. & P. 133; and R. v. Tyler and Price, [1838] 8 C. & P. 616.