Actus Reus in UK Law

They do not provide, as they might have done, that the Eagleton test is to be followed or that, as Lord Diplock suggested, the defendant must have reached a point from which it was impossible for him to retreat before the actus reus of an attempt is proved. On the other hand the words give perhaps as clear a guidance as is possible in the circumstances on the point of time at which Stephen's "series of acts" begin. When that is will depend of course upon the facts in any particular case.

(a) The Crown is required to prove the ingredients which constitute the actus reus of the crime. Although different language is used to describe this concept, for present purposes, we respectfully adopt the suggestion in Smith & Hogan, Criminal Law, 8th Edition, at page 28, that it must be shown that the defendant:

Section 2 of the 1957 Act only comes into play where all the ingredients of murder are established against the defendant. Section 2 of the 1957 Act only comes into play where all the ingredients of murder are established against the defendant.

The purpose of section 4A, in my opinion, is to strike a fair balance between the need to protect a defendant who has, in fact, done nothing wrong and is unfit to plead at his trial and the need to protect the public from a defendant who has committed an injurious act which would constitute a crime if done with the requisite mens rea.

If there is objective evidence which raises the issue of mistake or accident or self-defence, then the jury should not find that the defendant did the "act" unless it is satisfied beyond reasonable doubt on all the evidence that the prosecution has negatived that defence.

Of course, a necessary ingredient of the crimes of murder and manslaughter is that the accused has by his act caused the victim's death. Even where it is necessary to direct the jury's minds to the question of causation, it is usually enough to direct them simply that in law the accused's act need not be the sole cause, or even the main cause, of the victim's death, it being enough that his act contributed significantly to that result.

No question of weighing its probative value against its prejudicial effect can arise; if believed, it is conclusive of the guilt of the accused. Like the evidence of acts done by the accused on the (assumed) instigation of the police as agents provocateurs, which was held in Reg. v. Sang not to be subject to the exclusionary discretion, it is evidence of conduct by the accused which in itself constitutes the offence charged and is given by a witness who himself observed that conduct.