In order to bring a whistleblowing claim, a worker must be able to demonstrate that they reasonably believed that their disclosure was “in the public interest”.

In the case of Underwood v Wincanton plc, Mr Underwood was an HGV driver and together with three of his colleagues, he submitted a written complaint regarding the way in which overtime was allocated among drivers. There was a suggestion that drivers who were granted less overtime were seen to be awkward because they had raised concerns regarding the safety of vehicles. Mr Underwood was then dismissed and he claimed he had made a protected disclosure.

The EAT in this case followed the case of Chesterton (where a group of 100 senior managers was sufficient to satisfy the public interest test). It held that the definition of the public could be a subset of persons employed by the same employer on the same terms and therefore having the same interest in a matter raised by another employee. Therefore, a dispute between Mr Underwood and his fellow employees and their employer could be said to be potentially in the public interest. The EAT also confirmed that disputes relating to terms and conditions of employment could be in the public interest.

This decision seems to be inconsistent with the purpose behind the inclusion of the public interest test in June 2013, which was meant to prevent employees seeking whistleblowing protection in relation to matters regarding their own contract.

The Chesterton case is being appealed to the Court of Appeal but is not due to be heard until October 2016. In the meantime, companies should bear in mind that cases involving individual contractual disputes affecting only a small group of employees are likely to be held to be in the public interest.

Therefore, employees making such a protected disclosure will be protected under whistleblowing legislation.