Supreme Court of United Kingdom– Deciding on an important issue concerning the mental element of intent which must be proved when a defendant is accused of being a secondary party to a crime and whether the common law took a wrong turning in two cases, Chan Wing-Siu v The Queen [1985 1 AC 168 and Regina v Powell and English  1 AC 1 wherein it was held that the mental element required of the secondary party is simply that he foresaw the possibility that the principal might commit a second crime (accessory liability), the Court by a majority concluded that the appeal should be allowed as Chan Wing-Siu and Powell and English did take a wrong turning and the introduction of the principle was based on an incomplete, and erroneous reading of the case law, coupled with generalised and questionable policy arguments.
The appellants were each convicted of murder after directions to the jury in which the trial judges sought to apply the principle deriving from Chan Wing-Siu. In these appeals the court has been asked to review the doctrine of parasitic accessory liability. The Court had to deal with law of secondary liability for crime which concerns the person who did not himself forge the document, fire the gun or stab the victim but who is said to have encouraged or assisted the principal to do so (joint enterprise). An important contention raised was that Chan Wing-Siu makes guilty those who foresee crime B but never intended it or wanted it to happen.
Justifying the need to take a different approach, the Court observed that the law in this field has always been a matter of the common law rather than of statute, and so it is right for the courts, which have created it, to investigate whether a wrong turning was taken. The Chan Wing-Siu principle extends liability for murder to a secondary party on the basis of a lesser degree of culpability, namely foresight only of the possibility that the principal may commit murder but without there being any need for intention to assist him to do so. The Court reasoned that the correct rule is; foresight is simply evidence of intent to assist or encourage, which is the proper mental element for establishing secondary liability The Court in a unanimous judgment held that the law must be set back on the correct footing which stood before Chan Wing-Siu and that the mental element for secondary liability is intention to assist or encourage the crime. [R v. Jogee,  UKSC 8, decided on 18.2.2016]