The appellants participated in strike action for one full day in November 2011. As a result, the respondent withheld part of their salary. Their contracts of employment incorporated terms relating to working time from a collective agreement known as the Red Book. The appellants argued the formula used to calculate the deduction was inaccurate, stating the correct calculation was 1/365 of their annual pay as opposed to 1/260.

The Red Book stipulates that teachers will be required to work up to 195 days a year of ‘directed time’. This includes teaching and other duties as specified in their contract of employment. In addition to directed time, a teacher is required to work an unspecified amount of ‘undirected time,’ owing to the wide range of responsibilities involved. The appellants regularly performed these undirected duties outside their normal working hours, for example, in the evenings and on weekends.

The appellants, relying on s.2 of the Apportionment Act 1870, argued their pay should accrue not only at a daily rate but also at an even rate. Lord Clarke, giving a unanimous decision, concluded a formula of 1/365 was ‘broadly fair’ as the work of a teacher is divided throughout the year. The Court confirmed it is not limited to when a teacher is undertaking the specific tasks as outlined in their contract of employment but includes undirected time, such as the marking of papers, preparing lessons, preparing teaching material and other duties that are reasonably required:

“In the context of an annual contract in which payment is monthly and, given the wide variety of work carried out, whether directed or undirected work, where there is no distinction between days upon which work is carried out and days upon which work is not carried out, the natural effect of the Act is that, as submitted on behalf of the appellants, the apportioned part of his salary on the day he was on strike was the same as any other day, namely 1/365 of his annual salary.”

The Apportionment Act applies where contracts do not have specific rules on how pay should be apportioned for various purposes and may not be applicable where workers do not work outside set days or where a rule on deductions is expressly written into terms and conditions of employment.

Full decision:
https://www.supremecourt.uk/cases/docs/uksc-2015-0142-judgment.pdf

As always, UK Supreme Court decisions are summarised on YouTube:
https://www.youtube.com/watch?v=caZ3i46WAFA