However, it upheld the tribunal's finding that Merton Borough Council had an "indisputably legitimate" business need to force Celestina Mba, a former care worker in one of its children's homes, to work on Sundays. Mba had claimed that she had been forced to leave her job because she had refused to do so.
"The use [in the Equality Regulations] of the disjunctive - 'religion or belief' – demonstrates that it is not necessary to pitch the comparison at a macro level," said Lord Justice Kay in his leading judgment. "Thus it is not necessary to establish that all or most Christians, or all or most non-conformist Christians, are or would be put at a particular disadvantage [by forcing them to work on Sundays]."
"It is clear ... that, for some Christians, working on Sundays is unacceptable. It is also clear that Mrs Mba's religious belief genuinely embraces that injunction. On this basis, it seems to me that the [employment tribunal] should have found that the application of the Sunday working [requirement] satisfied [the Regulations], with the consequence that the real issue in this case was whether the Council could show 'a proportionate means of achieving a legitimate aim'," he said.
The Employment Appeal Tribunal (EAT) made the same mistake when it upheld the original tribunal's findings earlier this year and described the tribunal's reasoning as containing "inelegant phraseology", he said. However, this legal error "made no difference" to the eventual outcome of the case, he said.
"After the most anxious consideration, I have come to the conclusion that, in all the circumstances of this case, and notwithstanding the legal errors to which I have referred, the decision of the [tribunal] that the imposition of the [Sunday working] was proportionate was 'plainly and unarguably right'," he said.
"In truth, once Mrs Mba failed to establish the more favourable terms of the contract for which she had contended and the Council had established that there was really no viable or practicable alternative way of running [the care home] effectively, there was only ever going to be one outcome to this case," he said.
Mba was employed as a care worker in a children's home under a contract which enabled the council to require her to work on Sundays. Merton accommodated her wishes as a Christian not to do so for two years, but later required her to work as contractually obliged. The original employment tribunal found that the council's aim in seeking to ensure that all full-time staff worked on Sundays in rotation was legitimate and objectively justified; a decision which has now been upheld by both the EAT and the Court of Appeal.
Indirect discrimination can occur where an apparently neutral provision is applied in a way that puts workers with a particular protected characteristic, such as gender or religions belief, at a particular disadvantage compared to those who do not have that characteristic. Unlike direct discrimination, an employer can defend a claim of indirect discrimination if it can show that the provision is objectively justified.