“Murder is unique in that it abolishes the party it injures, so that society has to take the place of the victim and on his behalf demand atonement or grant forgiveness; it is the one crime in which society has a direct interest.” W. H. Auden.
If Auden is right, it is something of an anomaly that there is no statutory definition of murder in English law.Murder remains a common law offence with a wide net. The offence is not confined to only those who kill with the intention of killing; an intention to cause serious injury will be sufficient. Serious injury need not however be life-threatening injury. Notwithstanding the abolition of joint enterprise by the Supreme Court in R v Jogee  UKSC 8], and attempts to narrow the mens rea of complicity, in practice the law still permits the net to be cast wide in multi-handed cases.
The partial defences of diminished responsibility, loss of control, and killings committed as part of a suicide pact may of course reduce murder to manslaughter. Similarly, the offence of infanticide will often obviate what would otherwise be a conviction for murder and allow a mother’s culpability for the killing of her child to be treated with the discretion it deserves. By contrast, however, duress is not a defence to murder and those who kill at the request of and with the informed consent of others for well-founded compassionate reasons, will also find themselves without a defence to murder.
In 2006 the Law Commission made proposals for a more limited law of murder, including the introduction of a statutory offence of first-degree murder [Law Commission, Murder, Manslaughter and Infanticide (Law Com 304, 2006)]. Fifteen years on there is still no inclination by any political party to make a legislative attempt to reflect the proposals.
Despite the range of circumstances in which killings occur, a conviction for murder will still not be confined to the most serious offending, judges will continue to be limited when it comes to sentence, and the route to murder liability, particularly as an accomplice, will inevitably continue to be problematic and in some cases unjust.