Mrs Mba, a practising Christian with strong Sabbatarian views, was a care assistant in children's home, run by the London Borough of Merton. Her job description included a requirement to undertake duties outside normal working hours as required by the shift rota, including weekends, bank holidays and sleeping duties. Though management had tried to accommodate her beliefs, her legal obligation was to work on Sundays if required. In the end, unable entirely to avoid Sunday working she resigned ‘with regret’ and brought proceedings in the Employment Tribunal alleging constructive unfair dismissal and indirect religious discrimination: the relevant law at the time was the Employment Equality (Religion or Belief) Regulations 2003. The Employment Tribunal (ET) rejected her claim and Langstaff J upheld that judgment in the Employment Appeal Tribunal, concluding that Article 9 ECHR added nothing of substance and that the ET had been correct to apply a quantitative rather than a qualitative test to assess the number of Christians impacted by the ‘provision, criterion or practice’ (PCP).

The primary point at issue in the Court of Appeal was paragraph 88 of the ET's original determination, in which the ET noted that the Council had tried to accommodate Mrs Mba and had been prepared to arrange shifts so as to enable her to attend church each Sunday, and that Sabbatarianism was not in any case a ‘core component’ of the Christian faith. Maurice Kay LJ observed that everyone accepted that Mrs Mba held sincere Sabbatarian beliefs not necessarily shared by other Christians; moreover, sensitivity to the diversity of beliefs between and within religions is something which flows from the respect that is accorded to the range of sincerely held religious beliefs. In his view the ET's application of the PCP had been erroneous because it had not been necessary to establish that all or most Christians, or even all or most nonconformists, would be put at a particular disadvantage: nevertheless, he dismissed the appeal.

Elias and Vos LJJ agreed that the appeal should be dismissed but on different grounds. The ET had not been wrong to have had regard to the overall impact of the PCP when assessing proportionality but similar considerations did not apply in relation to Article 9. The question was whether or not Merton's interference with Mrs Mba's rights was proportionate, given its legitimate aims. Article 9 claims could not be enforced directly in employment tribunals because breaches of Convention rights were not within their statutory jurisdiction; however, Elias J could see no reason why the concept of justification should not be read compatibly with Article 9 where that provision was in play: it did not matter whether or not Ms Mba was disadvantaged along with others, nor that her Sabbatarianism was not a core belief. The ET had been wrong to regard that factor as assisting the employer and, paradoxically, it was easier for an employer to accommodate a small group of employees with a particular belief than a large one. However, though the ET had been wrong to weigh in the employer's favour the fact that Ms Mba's Sabbatarianism was not a core belief, that error had not materially affected the ET's conclusion. [Frank Cranmer]