The Claimant, who works as an IT Systems Administrator for the Respondent and is an elected trade union representative, was issued with a formal oral warning for refusing a management request to delete an email distribution list used, amongst other things, for circulating communications from the trade union. The Claimant claimed that he had suffered a detriment within the meaning of section 146(1)(b) of the Trade Union and Labour Relations (Consolidation) Act 1992, and the main issue before the ET was whether the formal oral warning was given "for the sole or main purpose of preventing or deterring him from taking part in the activities of an independent trade union". The ET concluded that the refusal to take down the list, as well as the act of setting it up, was protected trade union activity, and that the main purpose of disciplining the Claimant was to penalise him for taking part in trade union activities. The Respondent appealed on a number of grounds, including that the ET had erred in characterising acts of deliberate misconduct as taking part in trade union activities, in failing to consider data protection issues, and in failing to apply the burden of proof on the Claimant to establish that his actions fell within section 146.

The EAT held that the ET was entitled to reach the conclusions that it had reached as to characterisation, that the Respondent had failed to raise any data protection issues in its evidence before the ET, and that the legal burden of proof was applied correctly.