Background
Warren Augustine worked as a private-hire driver for Data Cars Ltd in 2016, averaging 34.8 hours a week. Other drivers worked more than 43 hours a week on average, and his chosen full-time comparator worked more than 90 hours a week. All drivers paid the same fixed weekly “circuit fee” of £148 to access the company’s booking system.
Because the fee did not vary with hours worked, Mr Augustine paid more per hour worked and retained less pay per hour than his comparator. The Employment Appeal Tribunal held that this was less favourable treatment under the pro rata principle. But the tribunal, EAT and Court of Appeal dismissed the claim on the basis of McMenemy v Capita Business Services Ltd, which they understood to require part-time status to be the sole ground for the treatment.
The Court’s Holding
The Supreme Court allowed Mr Augustine’s appeal. Under regulation 5(2)(a) of the Part-Time Workers (Prevention of Less Favourable Treatment) Regulations 2000, part-time status need only be an effective cause of the less favourable treatment; it need not be its sole cause.
The Regulations deliberately use the established discrimination-law phrase “on the ground that,” not the Framework Agreement’s wording “solely because.” The domestic legislation was made under a broad power and could provide protection more favourable than the EU minimum. The word “only” in regulation 5(2) requires both the causation condition and the absence of objective justification to be met; it does not impose a sole-cause test.
The fixed fee inherently imposed a greater burden on Mr Augustine because of his lower hours. Other possible reasons for the arrangement, such as revenue generation or software constraints, did not prevent part-time status from being an effective cause; they could instead be relevant to objective justification or compensation. Data Cars had not relied on objective justification before the tribunal.
Key Takeaways
- A part-time worker need not show that part-time status was the sole reason for less favourable treatment.
- Part-time status is sufficient if it was an effective or substantial cause of the treatment.
- Other reasons for an employer’s practice may bear on objective justification, rather than defeat the discrimination claim at the causation stage.
Why It Matters
The decision resolves a UK-wide conflict over the causation test in part-time worker claims and disapproves the sole-ground approach adopted in McMenemy. It brings regulation 5 into line with the ordinary approach to direct discrimination, while preserving the employer’s statutory defence of objective justification.
Employers using flat charges, thresholds or benefits that depend on hours worked should assess whether those arrangements disadvantage part-time workers on a pro rata basis and, if so, whether the difference can be objectively justified.