Following the issue of a declaration of incompatibility by the Supreme Court, Parliament will now need to consider whether to amend trade union law to ensure compliance with Article 11 of the European Convention of Human Rights (ECHR).

What is the position under current UK legislation?

While employees have long had protection from being dismissed for taking part in lawful industrial action, trade union legislation does not provide equivalent protection against sanctions short of dismissal for employees (or workers) – such as disciplinary warnings, suspension or withdrawal of discretionary benefits.

Under section 146 of the Trade Union and Labour Relations (Consolidation) Act 1992 (TULRCA), workers do receive protection from detrimental treatment if the sole or main purpose is to prevent or deter them from taking part in trade union activities, or to penalise them for doing so. However, this protection only applies if those activities take place at “an appropriate time”. For these purposes, “an appropriate time” is defined as a time outside of the employee’s working hours, or within working hours with the employer’s consent. It would be very unusual for an employer to consent to industrial action which, by its nature, must generally take place during a worker’s working hours to be effective.

The upshot is that, until the dispute in this case, workers had not enjoyed protection from sanctions short of dismissal for taking part in industrial action, even where it was lawfully called.

What happened in this case?

Ms Mercer was a support worker at a social care charity and, at the relevant time, was a workplace representative for her trade union, Unison. In early 2019, there was a trade dispute over payments for sleep-in shifts and Unison lawfully called a series of strikes. Ms Mercer was involved in organising and publicising the industrial action, as well as in taking part in it herself. She was then suspended by her employer, during which period she continued to receive her basic salary but could not earn overtime pay or participate in the strike action.

Ms Mercer subsequently brought a complaint to the Employment Tribunal, alleging that her suspension amounted to a detriment imposed for the sole or main purpose of preventing her from taking part in trade union activities or penalising her for having done so, in breach of section 146 of TULRCA.

A reminder of lower court decisions

 The Tribunal dismissed Ms Mercer’s claim in so far as it was based on her participation in strike action, because taking industrial action was not a protected activity for the purposes of section 146. The Tribunal recognised that the absence of any protection from detriment short of dismissal would amount to a breach of workers’ right to freedom of assembly and association under Article 11 of the ECHR, but went on to conclude that section 146 could not be read in a way that was compatible with that right.

On Ms Mercer’s appeal to the Employment Appeal Tribunal (EAT), it upheld the finding that TULRCA’s failure to provide proper protection against sanctions short of dismissal for employees who take industrial action was a breach of their Article 11 rights. However, the EAT decided that it was possible to read section 146 in a way that would be compatible with those rights, by reading additional words into the definition of “appropriate time” so that it could include “a time within working hours when [a worker] is taking part in industrial action”.

The Government, as intervenor in the case, successfully appealed the EAT’s decision to the Court of Appeal. The Court of Appeal held that the EAT’s reading new words into the definition of “appropriate time” amounted to an impermissible judicial rewriting of TULRCA, as Parliament had purposely excluded lawful industrial action from the scope of activities protected by section 146. While the Court of Appeal agreed that section 146 might amount to an unlawful breach of Article 11 rights, it found that this raised a number of sensitive policy questions which could only be determined by Parliament. However, the Court of Appeal declined to issue a declaration of incompatibility under the Human Rights Act, on the basis that was not an appropriate remedy in relation to a ‘gap’ in the law and should be reserved for specific statutory provisions which were incompatible with ECHR rights.

Ms Mercer, supported by Unison, appealed the Court of Appeal’s decision on three grounds:

• the extent of protection provided by Article 11 to union members from detriments short of dismissal for taking lawful industrial action;
• whether section 146 could be read in a way that is compliant with Article 11; and
• if not, whether a declaration of incompatibility should be granted in respect of section 146.

What has the Supreme Court decided?

The Supreme Court has ultimately allowed Ms Mercer’s third ground of appeal, making a declaration that the failure of section 146 of TULRCA to provide any protection against sanctions short of dismissal for union members taking part in lawful industrial action is incompatible with Article 11 of the ECHR.

The Supreme Court held:

• The “right to strike” is protected under Article 11, though it is not an absolute right.

While it is not necessary for UK legislation to provide comprehensive protection for all workers from even the most trivial sanctions for participating in lawful industrial action, the failure of TULRCA to provide any such protection for striking workers against sanctions short of dismissal constituted an unjustified breach of their Article 11 rights. The judgment pointedly states that “section 146 of TULRCA both encourages and legitimises unfair and unreasonable conduct by employers”.

• The Supreme Court agreed with the Court of Appeal that section 146 could not be read in an ECHR-compliant way. They echoed the Court of Appeal’s conclusion that there would be multiple possible ways of rewriting section 146 to achieve compliance - each of which raised sensitive policy questions with important practical implications.
• Finally, the Supreme Court disagreed with the Court of Appeal’s conclusion that a declaration of incompatibility would be an inappropriate remedy because the interference with Article 11 arose from a ‘gap’ in the existing legislation rather than positively from a specific provision.

On the contrary, the Supreme Court found that section 146 was the sole statutory means available to Ms Mercer to enforce her Article 11 rights, but that redress was “blocked” by the conventional interpretation currently given to that provision. On that basis, the Supreme Court granted a declaration of incompatibility of section 146 of TULRCA with Article 11.

What will happen next?

While the declaration of incompatibility does not automatically render section 146 of TULRCA invalid or unenforceable (or mean that any specific sanction short of dismissal against striking workers is currently unlawful), it is now very likely that Parliament will legislate to introduce new statutory protections for workers participating in industrial action.

As emphasised repeatedly in the Supreme Court judgment, the scope and balance of any new protections is ultimately a policy choice to be taken by Parliament. It remains to be seen whether, for example, TULRCA will be amended to prohibit all sanctions short of dismissal against striking workers, or whether the new protections will only apply to the most draconian detriments and employers will continue to be permitted to take steps such as withdrawing discretionary benefits. Similarly, we await further guidance on whether any future protections would apply throughout the duration of industrial action or would be limited to only the first 12 weeks (as is the case for automatic unfair dismissal protection for striking workers).

However, we would expect that any legislative change will now take place after the general election. If elected, the Labour Party is committed to a sweeping overhaul of trade union law and may use this as a further opportunity to widen the legal protections given to union members.

What are the implications for employers?

Even whilst we await legislative change, this judgment will have significant implications for employers threatened by industrial action:

• Avoid treating striking workers less favourably: Employers should be careful to avoid treating workers less favourably for taking part in industrial action (other than by withholding pay during strike action, which remains permitted). While that already reflects existing industrial relations good practice, many unionised employers have long-standing practices of withdrawing discretionary benefits from employees who take part in industrial action or paying special bonuses to employees who continue to work during strikes. In light of the Supreme Court’s decision, practices of this kind are now at major risk of legal challenge.
• Reputational damage: although an employer won’t currently face legal consequences if it subjects striking workers to detriments, such action will likely cause employers reputational damage – both externally and amongst its own workforce. This would also likely have a detrimental impact on industrial relations.
• Legal claims: despite the Supreme Court’s decision, individuals who suffer a breach of their Article 11 rights will still need to bring litigation in the Employment Tribunals in the first instance and exhaust all rights of appeal before they can seek redress for a breach of their ECHR rights.

More generally, it is notable that the Supreme Court referred to a “right to strike” on 18 separate counts in the judgment. The UK courts have traditionally avoided recognising a general right to strike, and this appears to be the first occasion that the Supreme Court has held that workers enjoy such a right under Article 11. This decision may therefore have broader implications for the growing body of trade union litigation under Article 11 and may further embolden the union movement to bring future human rights based challenges to other statutory restrictions on industrial action.

Secretary of State for Business and Trade v Mercer [2024] UKSC 12 –judgment available here.