In R v Rahman  UKHL 45, Lord Brown began his speech by stating – “There are many more murderers under our law than there are people who have killed intentionally. The actus reus of murder is, of course, the killing of the victim; the mens rea (established in R v Cunningham  AC 566) is the intention either to kill the victim or at least to cause him some really serious bodily injury—grievous bodily harm as it used to be called, gbh for short. As this appeal illustrates, moreover, there is a further group of murderers too, those who did not intend even gbh but who foresaw that others might kill and yet nonetheless participated in the venture." Rahman is now the highest English authority on "joint enterprise" as applicable to murder. It establishes that where a principal offender committed an unlawful killing with the requisite intent for murder, a secondary party would be liable for murder on the basis of his foresight of what the principal might do and not on his foresight of the intention with which the principal might perform his act.
Criminal liability based on what is often referred to as “joint enterprise” is very problematic and was the subject of a Panorama programme in November 2009 – see “Joint enterprise: who is guilty.” Also see BBC - “We will come for you: gangs warned.”
In the recent case of Starfield Badza v R  EWCA Crim 1363, Badza had been convicted of murder of Billy Ward on the basis of “joint enterprise.” Ward was knifed many times and the evidence pointed to a co-accused Lubango as being the actual knifeman. Nevertheless, Badza was involved. The Court of Appeal applied the House of Lords decision in Rahman and dismissed Badza’s appeal.
Few would have any problem with the dismissal of Badza’s appeal. However, one wonders just how many people are now in jail for murder as a result of them being on the periphery of some serious act of violence. Did they all truly have foresight of what the other(s) might do? The law needs to send out a strong message to those who involve themselves in violence or who have potentially violent acquaintances. Nevertheless, is this strong message working injustice? Is there a case for law reform?