Sam Hallam and Joint Enterprise


The recent overturning of the murder conviction of Sam Hallam raises many questions; such as how did such a miscarriage of justice occur in the first place and why did it take so long for the case to be referred back to the Court of Appeal by the Criminal Cases Review Commission?

Another aspect of this and of many other cases awaiting a decision from the Court of Appeal is that Mr. Hallam was convicted under the principle of joint enterprise.  So what exactly is this principle and why has it given rise to so many appeals against conviction?

In England and Wales an offence may be committed by a principal or a secondary party. In many cases, particularly those involving attacks by large gangs or groups of people where one of the group, for example, produces a knife and stabs the victim, it may not be possible for the prosecution to identify the principle offender. This however will not save a defendant from a conviction based on the act of stabbing, provided that the jury can be sure that he or she was either the principal offender who stabbed the victim or a secondary party to that offence.

One way of being a secondary party to an offence is for an offender to have joined in and participated in an enterprise to commit an offence, in the course of which he or she either intended or realized that the offence committed by the principal offender would or might be committed.  This is the principle of joint enterprise under which Sam Hallam and many others have been convicted.

With some exceptions the secondary liability of a defendant is dependent upon and derives from the commission of the principal offence by the principal offender and in order to prove secondary liability the prosecution must establish:-

  1. Conduct by the defendant amounting to assistance to , or encouragement of, the principal offender:

  2. An intention to assist or encourage the principal offender to commit the principal offence;

  3. The defendant’s knowledge of the essential matters which constitute the principal offence.

It is the third of these requirements which causes many of the problems with the doctrine of joint enterprise.

By way of example let us consider a not unusual scenario in which the prosecution alleges that the defendant and the principal offender were involved in a joint enterprise to stab the victim to death in which the victim was stabbed not by the defendant but by the principal offender.  The defendant admits a common purpose to cause the victim really serious harm but denies having the intention to kill the victim.

In the above case the jury will have to decide whether the act of the principal offender was committed within the scope of a common purpose joined by the defendant or was it a fundamentally different act as no doubt the defendant would argue at the trial.  In other words, did the defendant know of a real possibility that the principal offender would use a knife with the intent required for murder?

Such cases are fraught with difficulty both for the judge directing the jury and for the jury endeavoring to apply the judge’s directions.  For example, the jury will have to decide whether the defendant took part in an attack on the victim intending that he or she should be killed; in which case the defendant is guilty of murder, or if they are not sure of that, whether wounding with a knife was within the scope of the criminal enterprise in which the defendant participated, in which case the defendant is guilty of murder or manslaughter.

The defendant will be guilty of murder, as part of a joint enterprise, if wounding with a knife was within the scope of the criminal enterprise in which he or she joined and he or she realized that there was a real possibility that the victim would be stabbed by one of the group with intention to cause really serious bodily harm or death.  The defendant will be guilty of manslaughter if the jury are sure that wounding was within the scope of the enterprise but not sure that he or she realized that one of the group would or might act with intent to cause really serious bodily harm or death.

There is much concern about the doctrine of joint enterprise and many are calling for it to be reformed or clarified. Only time will tell whether it continues in its current form.

Andrew J. Hobson
Solicitor Advocate
Hine Solicitors

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