"The evidence of the two supergrasses is manifestly tainted, in the sense that it cannot be above suspicion because of the close involvement of Mackay with Detective Constable Price and Superintendent Brown."
"Once the suspicion of perjury starts to infect and permeate cases in which the witnesses have been involved and which are closely similar, the evidence on which the convictions are based becomes as questionable as it was in the cases in which the appeals have been allowed. It is impossible to be confident that had the jury convicting the appellant known the facts and circumstances in the other cases in which the police officer had been involved, they would have been bound to convict the appellant. In our view, that is the appropriate test."