A couple of months I highlighted covered Department of Business, Energy and Industrial Strategy’s position that an employer may well act appropriately if they issue a worker a warning if that worker takes part in a campaign of strike action called by a trade union. Thankfully, BEIS’ argument – despite the fact that BEIS is the Government department responsible for protecting trade union rights – did not win the day.

The relevant facts of Mercer v Alternative Future Group Limited (2021) are that the claimant, who was also a representative of Unison, helped to organise and took part in official union backed industrial action. Upon her return to work after that action her employer issued the employee a formal warning for those actions. Unsurprisingly the claimant challenged that decision alleging that the warning was a detriment imposed upon her because of her trade union activities. After all, what could be more clearly trade union activities than taking part in a strike!

The law restricting an employer from subjecting an employee to a detriment because of trade union activities is found in section 146 of the Trade Union and Labour Relations (Consolidated) Act 1986, or TULRCA as it is more commonly known. The issue in the case is that s.146 of TULRCA s not extend to protection of trade union activity which comprises of industrial action (here taking part in a union strike) except where the sanction is dismissal (because, that would fall under s.152 which does provide protection for workers who strike and are dismissed because of this). As the EAT noted this is not a new position although thankfully most employers are not so stupid as to try to discipline workers for this reason. As long ago as 1980 that position had been set out in Drew v St Edmundsbury Borough Council [1980] (although strictly speaking these comments in Drew were probably obiter).

What differentiated the position in Mercer from Drew is that following the enactment of the Human Rights Act 1998 (HRA) the EAT was under a duty to interpret legislation where possible so as to be consistent with the relevant human right. So, at paragraph 31 it noted that:

as a matter of ordinary principles of construction, s.146 excludes industrial
action. The question is whether the legislation needs to be read differently, pursuant to s.3 HRA, in order to comply with the rights under Article 11, ECHR. To answer that question, it is necessary to consider Article 11 and the relevant ECtHR caselaw.

Article 11 of the European Convention of Human Rights (ECHR) provides a right for freedom of assembly, which includes the right to participate in the activities of a trade union. Article 11 is a qualified right which means that a state may impose restrictions so long as these “are necessary in a democratic society … for the protection of the rights and freedoms of others”.

Clearly, a state law that that gives an employer the green light to an employer to discipline a worker for taking part in a lawful strike – so long as they don’t dismiss them for this – imposes a substantial obstacle to a worker’s freedom to associate.

After analysing caselaw from the European Court of Human Rights (ECtHR) if found that this was not justified and that it was possible to interpret s.146 in a way that ensured that workers rights to take part in industrial action are protected. It did this by interpreting “appropriate time” as including time at which a worker is undertaking industrial action.

The upshot of Mercer is that it is now unlawful for an employer to impose any disciplinary warning on a worker because they took part in a union organised industrial action. This should give additional reassurance to workers that they cannot be penalised for exercising the human right to take part in industrial action. In Mercer this was a case about a disciplinary warning short of dismissal but the concept of detriment is much wider than that and, on the basis of Mercer, any adverse treatment may, if it it a penalty for taking part in strike action or a warning not to do so again in the future will be unlawful.

Mercer did discuss deductions of pay as one of the arguments against the claimant’s case was related to this and it is clear that any deduction of pay because a worker did not work the relevant hours is excluded from a detriment. You cannot, surprise surprise, therefore claim that an employer’s non payment of a day’s salary because you took part in a day long strike is a detriment. However, the case does pose interesting questions about whether the practice of some employer’s to invoke ‘partial performance’ measures whereby if a worker strikes, for example, for half a day they will withhold the full day’s pay can be challenged on this basis. Under contract law this is potentially lawful but there is at least an arguable case that any deduction of pay for hours that were actually worked can be challenged as a detriment within the newly broadened terms of s.146.