Supreme Court judgment: Secretary of State for Business and Trade v Mercer

Posted: 09/05/2024

The recent decision of the Supreme Court in Secretary of State for Business and Trade v Mercer marks a significant legal victory for Unison and the UK trade union movement. Employers can no longer treat workers detrimentally for taking part in industrial action, the Supreme Court having ruled that the current law is incompatible with the UK’s international legal obligations.

This decision will have a significant bearing on industrial relations in the UK for years to come. It amends law dating back to the early 1980’s. An employer’s ability to subject its staff to a ‘detriment’ – such as the loss of earning overtime or being disciplined – for the purpose of preventing or deterring their participation in a union-organised industrial action is now reduced.

Ordinarily, this would now be a matter for Parliament to remedy via legislation. However, this is highly unlikely to happen in a general election year. That said, a Labour victory will surely see the law swiftly amended to fix its incompatibility with the UK’s international obligations and address the Supreme Court’s decision. In the meantime, the ability of employers to disincentivise participation in industrial action has been curtailed.

Background

Mrs Mercer was a support worker and a workplace representative for Unison. In early 2019, Unison called a series of strikes to take place between 2 March and 14 May. Mrs Mercer was involved in planning and organising these strikes, took part in some related media interviews, and indicated an intention to participate in the strikes herself. On 26 March Mrs Mercer was suspended by her employer for nearly two weeks and subsequently disciplined. She was given a first written warning for abandoning her shift. On 23 August 2019, Mrs Mercer issued employment tribunal proceedings claiming that she had been subjected to a detriment (namely, suspension, inability to earn pay for the overtime she would otherwise have worked, and disciplinary action) for participating in the activities of a trade union.

Law:

Article 11 of the European Convention on Human Rights (ECHR) guarantees the right to freedom of assembly and the right of workers to form and join trade unions for the protection of their interests. Any restrictions on these rights must be prescribed by law and necessary in a democratic society. UK courts must interpret our domestic legislation compatibly with the ECHR. In doing so they may go beyond the normal principles of statutory construction, and supply missing words, provided this is consistent with a fundamental feature of the legislative scheme (a process known as 'reading down').

Employment Tribunal (ET):

The difficulty for Mrs Mercer’s claim was that taking part in industrial action is not one of the activities currently protected by UK law. Under the Trade Union and Labour Relations (Consolidation) Act 1992 (TULRCA), s. 146, workers are protected against detriments falling short of dismissal related to taking part in the activities of an independent trade union at an appropriate time. The scope of 'trade union activities' in that provision has been interpreted as not including industrial action. So while there is an absolute ban on dismissing employees for taking part in protected industrial action, UK law contains no ban on subjecting employees to a detriment short of dismissal for having done so. The ET held that UK law does not protect Mrs Mercer. As anticipated, Mrs Mercer appealed.

Employment Appeal Tribunal (EAT):

On appeal, the EAT held that UK law could be interpreted as protecting Mrs Mercer. The EAT suggested that the very fact that dismissal for participation in industrial action is protected whilst those taking part in official strikes have no equivalent protection for detriment short of dismissal, is an anomaly in the legislation. The EAT held that it was possible to read down section 146 compatibly with the ECHR by adding an additional limb to the definition of 'appropriate time' in section 146(2), namely '(c) a time within working hours when he is taking part in industrial action'. This was a significant moment for Unison and the UK trade union movement. However, this legal victory was short-lived as the then Secretary of State, Kwasi Kwarteng, intervened and appealed the decision to the Court of Appeal.  

Court of Appeal (CA):

The CA held that the EAT was wrong to read protection via the addition of a new sub-clause because this was not a case in which a section was incompatible with the ECHR, rather there was a gap in provision in our UK law. The CA held that, where there was such a gap in the law, and uncertainty arising from European Court of Human Rights case law, it was not possible for the EAT to add a new sub-clause. Therefore, until such time as the UK government amends our legislation, the CA determined that UK workers do not have protection from detrimental treatment for participating in industrial action. Understandably, Unison supported Mrs Mercer with an appeal to the Supreme Court.

Supreme Court: 

While sympathising with the CA’s view, the Supreme Court reached a different conclusion, and ruled that this was a case in which it was appropriate to make a declaration of incompatibility. Until the legislation is amended, section 146 TULR(C)A remains in force and effect. However, if the UK does not amend the legislation to bring it in line with our international obligations under the ECHR, this case can proceed to the European Court of Human Rights. 

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