Unfair dismissal – Determination whether dismissal fair or unfair. The employment tribunal had been entitled to conclude that it had been a reasonable response for a disciplinary panel to have concluded that the appellant head teacher's non-disclosure of her close relationship with a third party, who had been convicted of making indecent images of children, had not only amounted to a breach of duty, but had also merited her dismissal. Accordingly, the Supreme Court dismissed the appellant's appeal against the decision of the Court of Appeal, Civil Division, upholding that decision.