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What is murder?

There are two components of murder: Actus reus (the act of violence) and Mens rea (the intention behind the act).

The offence of murder in much of the UK is found in what is known as the Common Law. The Common law system in England and Wales is based on a system of judicial precedent. Precedent is the term used to describe that decisions of courts become binding over time. Common law is made up of judge-made law (known as case law) instead of statutes, which are passed in Parliament. When a decision is being made on a case, judges review previous cases to ensure that decisions that are made are in conformity with previous judgments.

There are two elements to the common law offence of murder and both are required to find that an accused person has murdered the victim:

1) Actus reus – This refers to the conduct of the accused. It describes what the defendant must be proved to have done (or failed to do), in what circumstances, and with what consequences in order to be guilty of a crime. E.g: The killing of a friend ‘Maddison’

2) Mens rea – This refers to the intention of the accused. Mens rea translates to ‘guilty mind’ in Latin and is the legal term used to describe the element of a criminal offence that relates to the defendant’s mental state and intention just prior to the act that resulted in death.

*Intention – This refers to the purpose or the aim (This is a straight-forward concept and should not be over-analysed).

In Cunliffe v Goodman (1950), Lord Asquith explained that intention “connotes a state of affairs which the party intending…does more than merely contemplate: it connotes a state of affairs which, on the contrary, he decides, so far as in him lies, to bring about”. In other words, this case law tells us that the accused needs to have intended to do the act, rather than to idly consider it.

Note: Curiously, in contrast to the offence of murder, attempted murder requires the presence of an intention to kill, not merely to cause grievous bodily harm. For murder, there is only the need to have intended an unlawful assault (that resulted in death) for a murder to be found.

*Death – A person is accepted to have died when he/she stops breathing, the heart stops pumping blood, and the brain ceases to function; ‘brain death’.

*Grievous bodily harm: This refers to serious harm to the body even if it does not pose a risk to the life of the victim.

NOTE: If the victim intends to kill but ends up killing another person, the defendant can still be guilty of murder due to the doctrine of transferred mens rea. They did intend to kill someone and they cannot escape guilt, just because they killed the wrong person. You cannot transfer mens rea (the intent to kill) if the accused intends to kill an animal, for example. and kills the victim instead. In this instance the accused may still be prosecuted under various provisions for negligence.

© University of Hull
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Introduction to Criminology

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