Whistleblower protection was changed in 2013, including the removal of requirement for the disclosure to be made in good faith and its replacement with a rule that the disclosure has to be (in the reasonable belief of the whistleblower) in "the public interest".  The novel question in Chesterton Global Ltd v Nurmohamed was what does this mean in practice?

The claimant was the MD of a branch of a firm of estate agents. He made allegations that senior management were misstating costs and liabilities across the whole office and branch network, with the result that the amount of commission payable to some 100 senior managers, including the claimant himself, was reduced. The claimant was subsequently dismissed and brought a whistleblowing claim.

The tribunal and EAT both rejected the employer's argument that the disclosure was not made in the public interest and therefore could not be protected under the legislation.

The EAT explained that the sole purpose of the amendment requiring disclosures to be made "in the public interest" was to close a loophole (identified in the Parkins v Sodexho case) that allowed workers to receive whistleblowing protection even where their disclosure was about individual breaches of their own contract of employment, with no wider public interest implications.  By contrast, the disclosures in this case related to matters that had potentially adverse implications for 100 senior managers.  Although the claimant was concerned most about his own position, he did have the other senior managers in mind too when making his disclosures.  As a group, they were a section of the public that would be affected by the issues he complained about.  This was enough to satisfy the public interest test. 

The decision indicates that the "public interest" barrier is not going to be one that is particularly difficult for a claimant to overcome.  The EAT specifically commented that the whistleblowing rules are designed to protect employees from unfair treatment for raising in a responsible way genuine concerns about wrongdoing in the workplace.  So as long as the issue being raised is a breach of contract that potentially impacts others, and the employee has this in mind when making the disclosure, the public interest test is likely to be satisfied. What is presumably no longer protected is the raising of an individual, stand-alone, grievance against an employer.