In the case of Mireku v London Underground Ltd, the claimant worked part-time as a Customer Service Supervisor under a job-share arrangement, alternating two weeks on and two weeks off with a colleague. Although the arrangement was supported locally, it introduced practical complications - particularly around overtime approvals - because Mr Mireku remained on the budget of one area manager (Paddington) while physically working in a different area (Whitechapel). This led to some confusion among managers about who could authorise overtime and how it should be funded.
In October 2022, Mr Mireku’s request to work overtime during one of his ‘off’ weeks was initially approved, then cancelled. He brought a claim alleging that he had been treated less favourably because of his part-time status.
The employment tribunal found that some earlier refusals to allow overtime were based on incorrect assumptions about job-share workers and did amount to less favourable treatment. However, those earlier incidents were found to be out of time and the tribunal declined to extend time.
As for the key incident on 19 October 2022, the tribunal accepted that the cancellation of overtime was due to genuine confusion around how the request should be processed - particularly because of the unusual position of Mr Mireku being managed in one area but funded from another. It was not, in the tribunal’s view, caused by his part-time status.
The EAT upheld that decision. It confirmed that in order to succeed in a claim for less favourable treatment, a part-time worker must show that their part-time status was the sole reason for the treatment. This reflects the approach taken in Augustine v Data Cars Ltd (a case we previously reported on), where the EAT reluctantly concluded that it was bound to apply this stricter test, despite recognising that a more flexible approach may better reflect modern employment protection.
In any event, the EAT held that the claim would have failed even if a broader test had applied. The tribunal’s findings clearly showed that the cancellation was not caused - even in part - by the claimant’s part-time status, but rather by a misunderstanding linked to budgeting arrangements. The claim also failed because the claimant had not identified a valid full-time comparator in relation to the specific incident complained of.
This decision offers several practical reminders:
Where bespoke working patterns are agreed, it is helpful to document how key processes like overtime approval will operate in practice, to avoid mixed messages and potential claims.