The Supreme Court and the Privy Council unanimously allowed both appeals against conviction for murder. In both cases the appellants were secondary parties who were present at or near the scene of the murder. In each case the actual murder was committed by a co-defendant. However in both cases the judge had directed the jury that it was sufficient if the appellant had foreseen (without necessarily intending) that their co-defendant would kill.
This form of liability has become known as parasitic accessorial liability (PAL), a term coined by Professor Sir John Smith QC in 1997, around the time of the decision in R v Powell and English  1 AC 1. The judge’s directions were derived from the decision of the Privy Council in Chan Wing-Siu v The Queen  1 AC 168, which was then applied as a matter of English law by the House of Lords in Powell and English and a number of subsequent cases.
In R v Jogee and R v Ruddock a joint sitting of the UK Supreme Court and the Judicial Committee of the Privy Council was held in order to consider the correctness of the PAL principle. The appellants contended that PAL was based upon unsound principles and had no proper foundation, and that it should therefore be held to have been an erroneous development of the law.
The Court unanimously concluded that the decisions in Chan Wing-Siu and Powell and English had indeed constituted a wrong turning, and the appeals were therefore allowed.
The Court’s reasoning is that these decisions unjustifiably departed from the well-established rule that the mental element required of a secondary party in a crime is an intention to assist or encourage the principal to commit the crime. The Court therefore concluded that the law should be set back on the footing which stood before Chan Wing-Siu. The mental element for secondary liability is intention to assist or encourage the crime.
Julian Knowles QC conceived the successful submissions and argued the appeal for the appellant Ruddock.