R v Sussex Justices, ex parte McCarthy ([1924] 1 KB 256, [1923] All ER Rep 233) is a leading English case on the impartiality and recusal of judges.
It is famous as a legal precedent in establishing the principle that the mere appearance of bias is sufficient to overturn a judicial decision.
"[1] In 1923 McCarthy, a motorcyclist, was involved in a road accident which resulted in his prosecution before a magistrates' court for dangerous driving.
The appeal was essentially one of judicial review and was heard at the King's Bench division by Lord Chief Justice Hewart.
Speaking for myself, I accept the statements contained in the justices' affidavit, but they show very clearly that the deputy clerk was connected with the case in a capacity which made it right that he should scrupulously abstain from referring to the matter in any way, although he retired with the justices; in other words, his one position was such that he could not, if he had been required to do so, discharge the duties which his other position involved.