The Claimant was employed by the Respondent. She was not a trained firefighter, and not employed in an operational firefighting role. As such, she was employed on what are called Green Book terms. Operational firefighters were employed on Grey Book terms. These were, in relation to aspects of their duties and obligations, more onerous, and in relation to remuneration, hours and holidays, more favourable, than Green Book terms. The Claimant claimed equal pay with regard to certain particular Grey Book terms, in respect of a period during which her comparators – who were both trained operational firefighters employed on Grey Book terms – were seconded to non-operational roles. She claimed that, in those roles, they were doing like work with her work in her own particular roles during the comparison period. The ET found that (a) the Claimant was doing like work with her comparators during that period; (b) the difference in the relevant terms was because of material factors reliance on which did not involve direct sex discrimination; (c) reliance on those factors did involve indirect discrimination; but (d) reliance upon them was a proportionate means of achieving legitimate aims. Accordingly the equal pay claim failed. The Claimant had resigned, and a complaint of constructive unfair dismissal also failed, because the ET found that there was no fundamental breach of the implied duty of trust and confidence, nor, since none fell to be implied, of an equality clause. The Claimant appealed.

The EAT dismissed the appeal for the following reasons: 1) One strand of the material factor defence relied upon was that the comparators were, during the period of their secondments, required to maintain operational competence. The ET did not err by failing to make findings that they in fact did not fully do so. Even if that was, to a degree, the case, which was to some extent (though not entirely) conceded, the ET was entitled to conclude that the Respondent’s requirement was genuine and could properly be relied upon in support of the Respondent’s legitimate aims; 2) The Claimant relied in particular on the fact that a group of Green Book employees in Head of Service Team (HOST) roles had received equal pay with colleagues on Grey Book terms in equivalent roles. The ET did not err by not concluding that this undermined the Respondent’s case that maintenance of the differential in respect of the Claimant was necessary and proportionate to its legitimate aims; 3) There was a challenge to the conclusion that the Claimant was not constructively dismissed, which contended that if, by reference to either or both of the first two grounds of appeal, the ET had erred in dismissing the equal pay claim, then it had also erred by not finding that there was a breach of the equality clause that would have been implied, had the equal pay claim succeeded. As the first two challenges failed, this challenge also failed. It was therefore unnecessary to the disposal of this appeal to consider whether, as a matter of law, any and every breach of an equality clause must be a fundamental breach of contract.