These key cases show how the protection of trade union collective bargaining is approached by courts and tribunals. In each case we summarise the circumstances of the dispute, the court’s application of the law to what happened, and the decision’s implications for organisations.

The cases should be read alongside our Trade union recognition and industrial action Q&As.

[2022] EWCA Civ 379
Issue: protection for trade union activities and industrial action

Since the 1970s, protection for workers who are treated detrimentally or dismissed for trade union activities did not extend to protection for those on strike or engaging in other industrial action.

Mercer was a support officer for a health and social care charity providing a range of care services across north west England. She was a workplace representative for her trade union, Unison. There was a dispute about payments for sleep-in shifts. Mercer was involved in planning and organising part of a series of strikes called by Unison. She had given some media interviews, in which she stated she would be taking part in the strike herself.

She was suspended because of her involvement. A key issue was whether preparing for a strike was a trade union activity because historically ‘trade union activities’ did not include preparing for, or taking part in, strike action. The matter reached the EAT which said that the legislation must be interpreted under our current Human Rights Act 1998 to include protection against detriment for taking part in, or preparing for, industrial action. The government intervened in the case and appealed against the EAT’s decision.


The Court of Appeal found in favour of the government and decided that Mercer was not entitled to pursue her claim under s146 of the Trade Union and the Labour Relations (Consolidation) Act 1992 (TULRCA). TULRCA does not protect against detrimental treatment (short of dismissal) for taking part in industrial action and this case shows it does not have to be interpreted in a way that is consistent with a right to strike.

Any restriction at all on the right to strike potentially interferes with the human right to freedom of association and assembly, which is protected in both the UK Human Rights Act 1998 and Article 11 of the European Convention on Human Rights (ECHR). The CA said that although TULRCA did not comply with these protected human rights, which could mean that both the employees’ right to freedom of association and the government’s obligations under the ECHR may be breached, it was Parliament that had to correct this and the courts could not read words into the legislation to give effect to human rights.


This is a significant decision because it confirms other court rulings that industrial action does not amount to trade union activities, and so is not protected against detrimental treatment by TULRCA. It also means that private sector workers are less likely to be protected if their employer treats them detrimentally (other than dismissing them) for participating in industrial action. Employers may still face tribunal claims based on human rights but striking workers will struggle to claim that TULRCA (s.146) protects them.

Even though limiting workers’ protection when participating in industrial action can be incompatible with the right to freedom of association and assembly (Article 11 of ECHR and UK Human Rights Act 1998), exactly what types of detriment could be protected is unclear in the light of this decision. For example, could an employer withhold a discretionary bonus or refuse promotions for striking? Do human rights protections apply to detriments for taking part in all industrial action or only official industrial action? And in cases of long-running industrial action, how long does that protection last?

In summary, employees dismissed for taking unofficial industrial are banned from making unfair dismissal claims. Even employees dismissed for official industrial action can only bring unfair dismissal claims under a limited number of exceptions. For example, dismissals resulting from industrial action are only unfair if the action is official and the dismissal occurs within 12 weeks of the employee joining that action, or where the dismissals occur because an employer is making an example of some striking employees, rather than dismissing all those striking as a group.

This case may be appealed again as the decision has a major impact on the bargaining positions of unions and employers. There is certainly an increase in case law in this area (see also a similar decision in Ryanair DAC v Morais and others 2021).

EA-2021-000275-DA (previously UKEAT/0025/21/DA)
Issue: protection for trade union activities and industrial action

Airline pilots participated in strike action called by their recognised trade union, BALPA. The employer withdrew concessionary travel benefits from the pilots for a year as a sanction. The pilots claimed this was detrimental treatment for taking part in industrial action at an appropriate time, contrary to Trade Union and Labour Relations (Consolidation) Act 1992 (TULRCA s.146). They also claimed this was ‘blacklisting’, contrary to the Employment Relations Act 1999 (Blacklists) Regulations 2010.


The striking pilots won. The EAT held that protection against detrimental treatment includes protection for participating in industrial action. The action in question did not have to be ‘protected’ industrial action (which provides dismissal protection for strikers) for the workers to be protected against detrimental treatment or ‘blacklisting’. The court also addressed some technical points such as what an ‘appropriate time' within working hours meant when the worker is taking part in industrial action. Basically, an appropriate time in s.146 TULRCA means a time within working hours when the worker is taking part in industrial action.


There are many implications of this case (and that of Mercer v Alternative Future Group Ltd and others (2021) below). In summary, it appears that there is a shift in protection for rights to strike, including:

  • A strike organised and called by a trade union counts as ‘trade union activities’ providing protection for strikers against detrimental treatment.
  • Any restriction on the right to participate in a trade union protest or strike is an interference with rights of assembly under Article 11 European Convention on Human Rights (ECHR).
  • The right to take industrial action is a protected, although not an essential, element of the Article 11 ECHR right.

As an additional consequence of recent cases, it appears that prohibiting proportionate deductions of pay for strikes is not an abuse of human rights but claims may follow about deductions of wages after strike action.

Some areas remain to be clarified, for example, whether other types of workers are protected if they participate in a trade union’s industrial action, and whether an employer can still sue for damages sustained during the industrial action.

The government has asked permission from the Court of Appeal to take the case to a further appeal. Until then, striking workers have a good argument that industrial action does amount to trade union activities and is protected against detrimental treatment under TULRCA.

(2021) UKSC 47
Issue: trade union recognition

A car component manufacturer offered increased pay and a Christmas bonus to staff through the Unite trade union. Unite members rejected this offer as insufficient when balloted on it. The company then attempted to bypass the union bargaining procedure by offering a Christmas bonus directly to the employees in return for them accepting the pay award and revised terms and conditions. A majority of employees accepted the offer. After a further offer and industrial action, collective bargaining resumed and agreement was finally reached.

It is unlawful for employers to make offers to union members if the employees’ acceptance would result in their terms and conditions not being decided by collective bargaining. The intention of this provision in the Trade Union and Labour Relations Consolidation Act 1992 is to prevent employers from undermining collective bargaining arrangements. Employers that have made such an offer outside of collective procedures can defend it in a tribunal, in the event of a claim, if they can show the sole or main purpose of the offer was not to avoid terms and conditions being determined by collective agreement.

If employers have made unlawful offers, each worker affected is entitled to a fixed compensation award under Section 145B of the Act.

Just under 60 Unite members brought employment tribunal claims that unlawful inducements had been made for them to give up their collective bargaining rights.


The Supreme Court eventually found that the employer had bypassed the agreed collective bargaining procedures and the union won its claim. The initial employment tribunal had found this too and awarded compensation of over £420,000 to the employees, representing the prescribed award (then £3,800) for each of the two offers made to each employee.

Implications for employers

This is the first time the Supreme Court has had to consider trade union collective bargaining rights, so this case has extensive implications for any employers with a unionised workplace. Trade union collective bargaining can lead to better pay and terms and conditions, and as union membership is rising as a result of the pandemic, employers should be alert to the rules governing collective bargaining.

The Supreme Court confirmed that where trade unions have collective bargaining rights, employers:

  • cannot ignore union bargaining procedures
  • must not make offers which, if accepted, would cause bargaining arrangements to be bypassed
  • must exhaust union bargaining procedures before they make offers directly to the workforce
  • must follow bargaining procedure and cannot opt in and out of the collective process as they see fit.

If employers genuinely believe that the collective bargaining process has been completed, then they will not be seen as trying to achieve the ‘prohibited result’ of bypassing the process if they make direct offers to the workforce. If, however, there was a real possibility that the terms would have been determined by collective bargaining without the employer’s offers, there is a risk the employer may be found to have unlawfully bypassed the system.

Unionised workplaces must conduct collective bargaining in good faith. Many offers will be unlawful if they are made before the bargaining procedures have been completed. Obviously trying to get employees to agree to give up collective bargaining permanently would be unlawful. But offers which, if accepted, stop even one term being decided by collective bargaining will be unlawful too.

Employers that make offers before completing the agreed bargaining procedures in good faith will be liable to pay the prescribed amount which, in 2021, is over £4,300 for each offer made to each employee.

(2002) IRLR 568
Issue: trade union recognition

This case entailed a 12-year legal battle which led to a change in the law. Wilson was a Daily Mail journalist. The editor wrote to all journalists saying the National Union of Journalists was derecognised. The newspaper offered a 4.5% pay rise to all staff who signed new contracts which gave up the right to have terms and conditions set by collective bargaining. Wilson refused to sign and was denied the pay increase.

In another case, Associated British Ports v Palmer and others (1995), similar issues arose when union members were offered a 10% pay rise if they agreed to give up collective bargaining rights. They refused to sign an agreement, received a lower pay rise and the union was later derecognised.

The matter eventually reached the House of Lord (then highest appeal court). The trade unionists lost at that stage. The decision was based on the reasoning that the employers’ actions to try and end collective bargaining was not seen as action on grounds of trade union membership or activities. The court also decided collective bargaining over employment terms and conditions was not an essential characteristic of trade union membership.


The matter then reached the European Court of Human Rights where the employer lost (this was the first case where trade unionists succeeded before the ECHR). The court held that the trade union employees’ right to freedom of association protected by Article 11 of the Convention had been infringed. UK employers were being allowed to use financial incentives to induce employees to give up important union rights which violated Article 11 and breached the rights of both the trade unions and employee members.

UK law, therefore, breached the Human Rights Convention by allowing employers to treat employees less favourably if they wanted to keep collective bargaining, which was an essential feature of union membership, and was allowing them to try and bring an end to collective bargaining. In summary, if workers were prevented from collective bargaining, then their freedom to protect themselves by belonging to a trade union becomes illusory. The government should ensure that trade union members are not prevented from using a union to represent them in attempts to regulate the relationship with their employers.


The government had to make changes to UK legislation to comply with this decision and the judgment had major implications for UK employment law governing representation at work.

The case decided:

  • unions must be free to organise industrial action in order to persuade an employer to undertake collective bargaining and listen to what the union has to say on behalf of its members
  • employees must be able to instruct their union to make representations to the employer or act in support of their claims
  • the state must ensure that trade union members are not prevented or restrained from using their union to represent them in attempts to regulate their relations with employers.

UK law still allowed employers to pay higher wages or other payments in return for giving up bargaining rights, if the higher wages related to services provided by the worker under the contract. The decision meant that treating employees less favourably if they were not prepared to give up collective bargaining rights was unlawful.

The case had far-reaching implications for employees and employers where unions were not currently recognised. Employers had to listen and respond to representations on pay, conditions and other issues from unions.

As a result of the case, the law on collective bargaining and statutory recognition procedures were changed in 1993 (known as the Ullswater amendment) and by the Employment Relations Act 1999. However, these changes were not enough because the law must protect employees against employers who act to end collective bargaining. This meant the law had to be changed again, which led to the Employment Relations Act 2004. This changed the law so that all workers were protected by the provisions on detrimental treatment for union membership and activities.

Please note: While every care has been taken in compiling these notes, CIPD cannot be held responsible for any errors or omissions. These notes are not intended to be a substitute for specific legal advice.

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