Legislating on Detriments for Taking Part in Industrial Action: Reflections on the Government’s Response to Consultation – by Ioannis Katsaroumpas

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1. Introduction

This reform had been long overdue. The failure of UK law to protect workers on strike from any detriments short of dismissal was a gap too blatant to ignore. Let alone defend. It entailed a zone of legal impunity for employer retaliation. And left the UK a restrictive outlier among European countries (see ETUI’s policy brief, Katsaroumpas et al 2025) and in profound breach of relevant human rights and ILO standards.

Recalling this context is essential for properly evaluating the new Section 236A of the Trade Union and Labour Relations (Consolidation) (TULRCA) 1992, added by the Employment Rights Act (ERA) 2025. It grants workers

‘a right not to be subjected as an individual to detriment of a prescribed description by any act, or any deliberate failure to act, by the worker’s employer, if the act or failure takes place for the sole or main purpose of preventing or deterring the worker from taking protected industrial action, or penalising the worker for doing so’ (emphases added).

Nothing is radical, of course, about this provision. It merely reduces the wide gap of UK law with what is common standard in other European countries and human rights. It also brings a measure of common sense and consistency. For the law already prohibited both dismissals and detriments for freedom of association and union activities ‘at an appropriate time’ (s. 146, TULRCA 1992). It was thus a profound anomaly that no symmetrical legal protection was provided for participation in industrial action, limited only to dismissals. By adding the missing fourth element in the protective edifice, the law at last signals the importance of tackling the vice of ‘hidden retaliation’ assuming the form of detriments liable to ‘nullify’ the right to strike (see Mercer, para.89),  consistent with the recognition of such risk regarding union activities.

The positive exercise of legislative drafting takes place under the strong shadow of human and labour rights. In Mercer, the Supreme Court pronounced the gap of UK law with Article 11 of the European Convention on Human Rights (ECHR). Yet it resisted an easy judicial fix by means of extending Section 146 to cover industrial action participation. Instead, it threw the ball into Parliament’s court by issuing a Declaration of Incompatibility (DoI) (under HRA 1998, section 4). Whatever reservations one might have about this position, from a constitutional perspective it can be defended as exemplary of the workings of a well-functioning ‘collaborative constitution’ (Kavanagh 2023): the three branches engaging in a soft institutional dialogue to remedy a human rights gap in a division of labour that displays due regard for each other’s expertise and competencies. As envisaged by proponents of the ‘political constitution’, the DoI served as the primary instrument that prompted and shaped this dialogic interaction. Thus conceived, Mercer can be read as democracy running its course: Courts diagnose the breach, Parliament supplies the fix.

The fix of 236A, however, left an essential quandary unresolved: what should count as a prohibited ‘detriment’? The question was to be settled by regulations (a feature typical of the ERA more generally; see further McGaughey 2026). In fulfilment of this task, the Government (DBT) published on 26 February 2026 the consultation document Make Work Pay: Protection from detriments for taking industrial action. It set out two possible formulations: a universal prohibition of ‘any detriment’ (except wage deductions); and a closed list of enumerated detriments.

The Government expressed a clear and strong preference for the former, evident in its characterisation as a ‘lead option’ (DBT 2026a, p.15). Such an inclination was also borne out in the assessment of options accompanying the consultation document (DBT 2026b).  

On 22 June 2026, the Government issued its consultation response (DBT 2026c), confirming the choice of universal prohibition. The draft regulations were also published, expected to come in force in October 2026. These regulations are necessary to give practical effect to Section 236A. Beyond defining detriments, the Government endorsed the addition of Section 236A to the list of rights for which tribunals may increase or decrease the award by up to 25% depending on whether an employer or employee unreasonably failed to follow the ACAS Code of Practice on Disciplinary and Grievance Procedure (due to the blog’s focus, this reform will not be further explored here).

This blog offers some reflections on the Government’s response, in light of the stated aim of addressing the pre-existing gap and comparative examples in other European countries (see further Katsaroumpas et al 2025). It argues that the Government’s choice of a universal prohibition of detriments marks a significant, well-evidenced and welcome step towards closing the gap. In particular, it prudently avoids several legislative traps associated with a closed list. However, if the objective is, as the Government put it in its response, to ensure that ‘workers get full protection against detriment when taking industrial action’ (DBT 2026c, p. 27), further work is outstanding. The forthcoming Regulations are a necessary yet not sufficient step.

The post draws attention to three major limitations, liable to seriously hinder the protective effect of Section 236A and the mileage gained by the universal prohibition:

1. the ‘sole or main purpose’ test operating as an overly restrictive filter;
2. the uncertain status of disproportionate wage deductions combined with an ambiguous deference to common law;
3. weaknesses in the ‘enforcement eco-system’ (for the term see Countouris 2024)  related to sanctions and the exclusively individualised model of access to litigation.

2. Prohibiting Any Detriments: A Universal Entry Point to Section 236A

Bogg and Ford aptly describe the ERA 2025 language that leaves the determination of detriments to secondary regulations as ‘recondite’ (Bogg and Ford 2024). While the material scope of the right was formulated as covering detriments of a ‘prescribed description’ (s. 236A, par. 1), paragraph 4 stipulated that regulations ‘may prescribe detriment of any description (instead of detriment of a specific description)’. Perhaps not an example of masterful legislative drafting in terms of clarity. Even leaving aside the possible redundancy of the parenthetical qualification and the fact that specificity is often a matter of degree. Yet beneath any drafting infelicities, it is possible to discern an intention to give Government broad latitude in the definition of detriments through secondary regulations.

As discussed, the Government made sense of this quite opaque statutory language as presenting a binary choice between two alternative options: a universal, open-ended prohibition of all detriments; and a closed list of enumerated specific detriments.

Interesting, no consideration was given to the possibility of a third, half-way option: a non-exhaustive list. In statutory language, it could assume the form of a specific list of enumerated categories of detriments introduced by a formulation ‘such as’ or ‘including’. Or, alternatively, by a ‘catch-all’ category after the list. For example, the legislator could insert the phrase ‘any other prejudicial detriment’ or ‘some other detriment’ (as in Italy where the law uses the expression ‘any other prejudicial treatment’; see further Katsaroumpas et al 2025). The ‘some other substantial reason’ catch-all category in the formally closed list of potentially fair reasons for dismissals (ERA 1996, s. 98) offers a well-known domestic example, albeit in a different context.

Nonetheless, overlooking the possibility of a non-exhaustive list was ultimately prudent and helpful. For any superficial appeal as a compromise, it would have conferred no obvious added value in practice. And it would even reduce legal certainty by inviting questions regarding analogies of any alleged detriments with the named detriments. For example, should they be similar in effect, in nature, in seriousness or in some other respect yet to be determined? Consequently, this choice would admit a considerable degree of guesswork and speculation regarding the precise criteria and legal test for their inclusion in the list. And, as the Royal College of Nursing rightly pointed out, the effect of a ‘catch-all category’ may be that of ‘essentially mov[ing] towards the logic of prohibiting all detriments’ (RCN Submission, p. 6).

So, the dilemmatic presentation of the choice as between universal prohibition and a closed list made matters far more straightforward. Quite unsurprisingly, the majorities of unions and employers/business associations lined up behind the former and latter respectively. It is notable, however, that a significant minority of employers/business organisations (10 out of 38) called for universal prohibition. By contrast, no union and only 2 (out of 12) workers opposed it (see DBT 2026c, p.8).

In its response, the Government ultimately confirmed its lead option of universal prohibition. In support, it invoked a broad set of justifications, including by noting with approval relevant submissions in the consultation. Central among them was the alignment of universal prohibition with the aim of ensuring ‘full protection’ against detriments (DBT 2026c, p.27) since it allows workers to participate in industrial action ‘without fear of repercussions’ (DBT 2026c, p.27). Alongside this protective rationale, an ‘anti-abuse’ justification was as prominent. Universal prohibition was deemed preferable because a closed list was more liable to abuse by ‘bad-faith’ employers (for this language see DBT 2026c, p. 11) resorting to those detriments not prescribed in the list. To quote the RCN submission, a closed list risked ‘becoming a ‘‘checklist for avoidance’’ rather than a deterrent to retaliation’ (RCN Submission, p.3).

Beyond these rationales, the Government relied on broader and more systematic rule-of-law justifications. It considered a universal prohibition as better able to promote legal certainty and ‘consistency’ with other areas of UK employment law which do not prescribe a closed list for detriments (including that of TULRCA, Section 146; see DBT 2026a, p.18). In addition, the Government identified in its response as a key advantage of universal prohibition that it would avoid the risk of the list being outdated, which would mean either the creation of protective gaps if retaliatory practices evolved or repeated legislative amendments (DBT 2026c, p.27). To use the consultation document’s own language, the universal prohibition would ensure, unlike a closed list, ‘future-proofing’ (DBT, 2026a, p. 18). The Government also viewed a universal definition of detriments as being to the broader benefit of workplace relations since it would ‘enable trust and stronger relations to be built between employers and workers’ (DBT 2026c, p.27)

Crafting a universal entry point to Section 236A fully aligns with the prevailing approach taken in other European countries. This point was highlighted in the consultation document, which recognised that the preferred approach ‘is consistent with other European countries, which have taken a broad approach to protection for workers taking industrial action’ (DBT 2026a, 16). As a general rule, they avoid setting out a closed list of prohibited detriments. By way of example, Portuguese law prohibits any employer acts against workers involving ‘coercion’, ‘harm’ or ‘discrimination’ for taking part in industrial action (see Katsaroumpas et al 2025).  

In doing so, the Government successfully avoided at least three major legislative traps.

The first is doctrinal dilution. Section 236A architecture rests on two, logically sequential and distinct, requirements: (i) whether the worker has suffered a ‘detriment’ as an individual (detriment requirement); and the employer’s ‘sole or main purpose’ being retaliatory – that is to prevent, deter or penalise strike participation (purposive requirement).

A closed list, as proposed by many employers and business associations, concealed the risk of conflating – or even collapsing – the two. This peril becomes intelligible on a closer inspection of the underlying arguments. Summarising the employers’ submissions, the Government’s consultation response document noted that they argued that a universal prohibition of detriments ‘could significantly restrict employers’ ability to make routine or necessary business decisions around the time of industrial action’ (DBT 2026c, p.11). And when discussing the content of a closed list, they suggested that the inclusion of detriments ‘should depend on whether the detriment is punitive or part of normal business process’ (DBT 2026c, p. 19). This criterion aligned with a broader distinction they purported to draw, between ‘ordinary’ business decisions (such as removing promotion opportunities) and punitive/legitimate detriments (DBT 2026c, p. 20).

Such a position and argumentation carried a major risk: to confuse the two requirements. To begin with, it is not possible to determine, in advance and in the abstract, whether a business decision is ‘normal’ or ‘ordinary’ without interrogating the specific functional context and the underlying employer purposes. Any such determination follows, and cannot precede, the application of the purposive requirement. The same holds in respect to whether the alleged misconduct is genuine; this cannot be determined a priori as part of the general exercise of defining a closed list of detriments at the level of regulations. And if an exclusion was provided regarding ‘genuine misconduct, where unrelated to participation itself’ (DBT 2026c, p. 20 emphasis added), it would add a confusing duplication of considerations which belong to the purposive requirement at the detriment level thereby imposing a dual evidentiary burden on workers. Determining whether a misconduct is ‘unrelated to participation’ would require an inquiry into the employer’s purpose to establish the absence of any relationship to strike participation. This would produce the absurd and irrational outcome, outrageous from the perspective of proper statutory construction, that identical considerations would effectively be double-counted in the determination of both the detriment and purposive requirements.

Moreover, the references to ‘routine’, ‘necessary’ or ‘ordinary’ business decisions appear to proceed on the assumption that such decisions are mutually exclusive with what is termed as ‘punitive’ detriments. This, however, does not always need to be the case. An employer may have already taken a business decision (for example, reducing voluntary overtime due to an anticipated drop in business demand) but subsequently use it to penalise workers taking part in an industrial action announced thereafter. In short, the proper and sole domain of determining such questions is ex post at the level of the purposive requirement on a case-by-case basis, rather than ex ante at the general level of defining the list.

The danger of infecting the detriment test with purposive considerations should a closed list be adopted was accentuated by Lady Simler’s position in Mercer. When discussing the scope of detriments to be prohibited under Article 11 ECHR, she stated that:

‘In my judgment the state’s positive obligations under article 11 do not require it to confer universal protection in all circumstances to all workers against any detriment (however slight) intended to dissuade or penalise them from participating in a lawful strike […] There may be circumstances where it is permissible to impose a detriment for participating in a lawful strike action where employees have necessarily acted in breach of contract, particularly where the manner of the breach is harmful or disruptive’ (Mercer, para. 83)

Bogg and Ford rightly observed that here LJ Simler ‘appears to be eliding ‘‘detriment” and “purpose”’(Bogg and Ford 2024). The manner of the breach (‘harmful’ or ‘disruptive’) is of potential relevance to the purposive and not the detriment requirement. Courts are accustomed to making such determinations. For instance, in whistleblowing cases the judiciary routinely draws very fine distinctions between prohibited detriments arising from the protected disclosure ipso facto and those from abusive conduct or manner of disclosure when interrogating the employer’s reasons and motivations. Doctrinally, the demarcation is governed by the ‘separability’ principle which asks whether the conduct was ‘inseparable’ from the act of disclosure (see Kong v Gulf International Bank (UK) Ltd, 2022 EWCA Civ 941).

This brings us to the second trap, avoided by the Government’s choice of universal prohibition. It pertains to the risk that the Government would, almost unwittingly, (mis)interpret Article 11 via Mercer as requiring the exclusion of some detriments beyond proportionate wage deductions and thereby by extension a closed list. One might also reach the same conclusion by applying a ‘fair balancing’ requirement derived from Article 11 case law. Such an interpretation would of course rest on a narrow scope of the balancing assessment, confined to the definition of detriment without taking account the fair level of balancing undertaken at the purposive stage by the restrictive ‘sole or main’ purpose test. Fortunately, the Government declined to tread this dangerous path. To be sure, it did not state unequivocally that universal prohibition constitutes the sole option compatible with Article 11. But neither did it reach the opposite conclusion that Article 11 mandates a closed list, possibly by using LJ Simler’s position mentioned above as an intermediary.

And a closer scrutiny of the Government’s response reveals that it does not consider Article 11 as neutral between the two options. Rather, it performs a discrete yet critical role in support of universal prohibition as more compatible with Article 11. Such a role was baked into the Government’s stated aim of reducing the ‘risk’ of further litigation with regard to Article 11. This is because the risk is presumed to be greater under a closed list given its perceived propensity to generate further gaps vis-à-vis Article 11.

In addition, the Government appeared to advance a trickier proposition based on Article 11 in the February consultation document. This derived from a particular interpretation of Article 11 as imposing a clear obligation on public service employers to prohibit any detriments, in contrast to private sector employers to whom it does not apply ‘in the same way’ (DBT 2026a, p. 19). This statement dropped a faint hint that a closed list might be compatible with (but not required by) Article 11 in the private sector. However, in a subtle twist, the Government identified the resulting disparity between public and private sector employees as a disadvantage of the closed list. The disparity is then invoked to support the levelling up of protection for all employees as a desirable objective (DBT 2026a, 19). In its implications, this was a double-edged argument: on the one hand, it mobilised disparity as a ground against a closed list; on the other hand, it risked implicitly endorsing a restrictive interpretation of the permitted detriments in the private sector under Article 11. Interestingly, and probably for the best, this argumentation and reading of Article 11 did not reappear in the Government’s consultation response.  

Third, rejecting a closed list presciently spares the legislature considerable time and energy. The latter would otherwise need to be expended for complex and highly indeterminate assessments for the criteria for including specific detriments and the appropriate level of specificity at which they should be defined. These include debates regarding the ‘gravity’ of each detriment as a potential criterion (which on its own could disregard their potential cumulative effect). In the February consultation document, the Government noted that a closed list approach would allow ‘to prohibit the most egregious detriments, while not preventing those that may have less impact on a worker’ (DBT 2026a, p. 18; emphases added). This sentence already puts forward tests of ‘seriousness’ and ‘de minimis impact’. Besides the fact that they are not exact opposites as implied (‘egregious’ concerns the outrageous character or gravity of the detriment; ‘less impact’ relates its effect on the worker), they can unduly restrict the scope of prohibited detriments. The Government also contemplated a range of possible approaches, from specifying categories of detriments to ‘detriments based on the level of severity of their impact on an individual worker’ (DBT, 2026b 6). Overall, as Unite rightly noted in its submission, a closed list would generate ‘satellite litigation on whether specific actions amount to a detriment’ (Unite Response, Answer to Q3).

To be sure, this does not mean that finding a detriment under the universal prohibition is always a clear-cut and straightforward undertaking. Case-law would most likely revert to the standard definition of detriment as ‘disadvantage’, modelled on the determination of detriment in anti-discrimination law. This sets a relatively low bar. As reaffirmed in Shamoon, ‘a detriment exists if a reasonable worker would or might take the view that the [treatment] was in all the circumstances to his detriment’ (para. 35, citing Ministry of Defence v Jeremiah [1980] QB 87). It is crucial to stress that the test adopts a worker-centric perspective on the existence of detriment. The primary focus is placed on how a reasonable worker would interpret the disadvantage in light of the full context (‘all the circumstances’). While a mere sense of grievance does not suffice, neither is it necessary for the worker to have suffered physical or economic consequences (Shamoon, para. 35).

The universal prohibition encompasses a diverse range of detrimental conduct. Its precise scope is flexible and open-ended, both virtues lying at the heart of the appeal of the universal prohibition in the first place. By way of example, it almost certainly covers bullying, harassment and intimidation as well as the withdrawal of benefits, denial of promotion opportunities, exclusion from important meetings, loss of training opportunities or arguably even an unfavourable office move.  One can only speculate as to the full range of detriments that may be covered. It seems not a stretch to argue that a captive meeting at which an employer urges staff not to participate in future industrial action, citing the company’s financial difficulties and hinting at potential loss of overtime as a result, would amount to a detriment if perceived as such by workers.

An interesting question arises with regard to defensive lock-outs, that is when an employer shuts down its business as a means of retaliation against actual or threatened industrial action. Can the case be made that they fall within the scope of ‘detriments’ under the universal prohibition? Since, by definition, these instances involve a retaliatory ‘sole or main’ purpose (preventing, deterring or penalising industrial action’), the question of whether they qualify as ‘detriments’ can prove determinative of their overall legality under Section 236A.

Answering this question is by no means straightforward and one must proceed with extreme caution. To answer it in the affirmative, two conditions need to be satisfied sequentially: (i) the existence of a disadvantage amounting to a detriment; (ii) that the worker was subjected to the detriment ‘as an individual’.

The first condition is perhaps easier to satisfy. Under Shamoon, it is at least arguable that a reasonable worker would regard a defensive lock-out as constituting a disadvantage capable of amounting to a detriment. This is due to the loss of pay and employment opportunities. Nor does the express exclusion of wage deductions avail the employer here. This is because it shall be read as covering cases where wage deductions are direct responses to a worker taking part in industrial action and not arising due to a defensive lock-out.

Whether defensive lockouts meet the ‘as an individual’ condition, however, is less definitive.  In the event of a universal lockout, can it be claimed that a worker is subjected to the detriment as an ‘individual’? Or can the employer rebut this by arguing that the lock-out was a collective sanction directed at the workforce as a whole in the course of the industrial relations strife, with individual workers merely caught in the crossfire but not targeted as individuals?

Here the quite cryptic ‘as an individual’ qualification forces us into the somewhat artificial and Procrustean exercise of distinguishing between the ‘individual’ and ‘collective’ dimensions of employer retaliation (on the broader theoretical problem of ‘individualism’ and ‘collectivism’ in collective labour law see Bogg 2017). If an employer subjects all workers to the detriment of a defensive lock-out, is it individual or collective retaliation?

To answer this question, particularly in light of the paucity of case-law, interrogating the legislative origins of the qualification is helpful. It first appeared in Section 53 of the Employment Protection Act 1975. The latter protected workers against detriments for union membership and activities (the forerunner of Section 23(1) of the Employment Protection (Consolidation) Act 1978). What is crucial, however, is that it was introduced as a direct response to the previous judgment Post Office v. Crouch ([1974] I.C.R. 378). In this case, a union officer successfully argued that the refusal of union facilities constituted a breach of Section 5 of the Industrial Relations Act 1971 which had made employer discrimination against a worker by reason of exercising any of his/her statutory rights an unfair practice. Crouch was seen as going too far, creating the risk that workers could merely recast what are measures against the union as instances of individual discrimination. This was what the ‘as an individual’ qualification sought to avoid. That is, to preclude claims by individual workers merely deriving detriments from employer actions targeted against unions leading to a loss of institutional rights in their capacities as union officers or members. LJ Nicholls in the National Coal Board v Ridgway [1987] I.C.R. 641 adopted this position. Noting the origins of the statutory formulation in response to the Crouch judgment, he stated that:

‘the expression “as an individual” in what is now section 23 of the Act of 1978 was intended to preclude adverse action taken against a union being treated ipso facto, on the reasoning adopted in the Crouch case, as action taken against the employee. Adverse action taken against a union is not, by reason only of any consequential effect it may have on members or officers of the union, to be treated as action against individual employees. To be within the section the action has to affect the employee otherwise than merely qua member or officer of a union. But an employee’s pay comes to him as an individual employee and not as a member of a union, even if its amount may be affected by negotiations between his union and his employer. Indeed, I find it difficult to think of an action, short of dismissal, which could be taken by an employer against an employee which could more obviously qualify as action taken against him as an individual than a reduction in, or a failure to increase, his pay (Ridgway, 658)’. (emphases added).

This statement could furnish a sound, authoritative basis for interpreting the content of the ‘as an individual’ qualification also in Section 236A. On this reading, the qualification is meant to exclude only ipso facto cases where an adverse action is taken against a union with workers suffering incidental, detrimental consequential effects of the loss of institutional rights merely in virtue of union membership (as for example through the withdrawal of union recognition). By contrast, where the worker is affected otherwise then the worker can be deemed as being subjected to the detriment as an individual.

Admittedly, the dividing line is not always sharp. It is nevertheless plausible to derive from this an interpretation of the qualification broadly consonant with the position developed in Croatian case-law. According to the latter, legal protection from detriments short of dismissal only excludes under the objective disadvantage test, ‘abstract institutional disadvantages, such as loss of union power or negotiating leverage’ (see Katsaroumpas et al 2025).

Consequently, the effects of lockouts on the terms and conditions of employment on individual workers can bring it within the definition of detriment as an individual notwithstanding that the employer deploys the lock-out as a collective means of retaliation. This finding is bolstered by LJ Nicholls’s position in Ridgway. He expressly identified reductions in individual pay as an example of individual actions taken ‘against an individual’, even where they were subject to determination by collective negotiations (Ridgway, 658). It does not seem a significant interpretative stretch to extend this to a defensive lock-out.

To be sure, this should not be taken as implying a categorical certainty that defensive lockouts qualify as detriments under Section 236A. The claim advanced here is far more modest: there is now a case to be made that defensive lockouts can qualify as detriments under Section 236A to be scrutinised further by labour law scholars and practitioners.

3. The Linkage Gap: The Sole or Main Purpose Test as an Overly Restrictive Filter

The prohibition of ‘any detriments’ ensures that the two inquiries, on the ‘detriment’ and ‘purposive’ requirements, remain distinct. However, given the Government’s stated aim of securing ‘full protection’ of workers on strike against detriments, it is essential to recognise the sole or main purpose test’s function as an overly restrictive filter.

Admittedly, any legal framework against detriments should designate some construction of the requisite linkage between a detriment and industrial action. This issue could be easily trivialised as a mere technicality. But, in practice, the precise configuration of the link holds crucial significance for the overall strength of the legal protection. The latter can be factored into the decision-making of bad-faith employers intent on repressing industrial action, ‘rationally’ calculating the likelihood of their conduct being found illegal as part of a narrow ‘cost-benefit’ calculus.

Before turning to Section 236A, it is useful to consider some examples of how this link is configured in other European countries. It may take the form of strike participation being an ‘essential motive’ (Germany); as a requirement or ‘causality’ (Italy); or demanding that the detriment was ‘on the grounds’ of strike participation (Portugal). In Croatia, the ‘but for’ test is considered applicable, that is, asking whether the detriment would have occurred but for strike participation (see Katsaroumpas et al 2025).

Within this spectrum, Section 236A occupies a position closer to the restrictive end (see Katsaroumpas et al 2025). The required link places a particularly demanding burden on workers. This primarily stems from the fact that the prohibition depends on whether the employer’s ‘sole or main purpose’ in imposing the detriment was to prevent, deter or penalise industrial action participation. Such a formulation mirrors Section 146. Fair arguments can therefore be made in favour of consistency and the presumed ‘familiarity’ of employers with the legal test (DBT 2026c, p. 28). However, familiarity should not breed insensitivity to its highly restrictive nature.  

The test in turn comprises two distinct parts. The first consists of what is in effect an employer-centric interrogation of the employer’s purpose. Drawing on case-law in the context of Section 146, purpose can be understood as ‘connot[ing] an object which the employer desires or seeks to achieve’ (see Bone v North Essex Partnership NHS Foundation Trust [2016] EWCA Civ 45, LJ Bean). In the context of Section 236A, the relevant object is to penalise, prevent or deter participation in industrial action.  This formulation is sufficiently broad to tend to directions of the temporal chain: both backwards, that is a detriment after industrial action (‘penalising’); and forward, that is a detriment before a future industrial action (‘preventing’ or ‘deterring’). Notably, the ‘deterring’ language lowers quite significantly the bar of the purposive effect to that of making industrial action participation less attractive (or more onerous) for workers.

What makes the test overly restrictive, however, is the requirement that the employer’s retaliatory purpose should be the ‘sole or main’ reason for the detriment. It is revealing of the restrictiveness of the filter that employers are free to subject workers to detriments in retaliation for industrial action participation as long as the retaliatory motive is not the ‘sole or main’ purpose.

Here it is important to recall that the origins of this formulation do not lie in the Thatcherite period but in the Employment Relations Act 2004 (amending the TULRCA 1992) under Tony Blair’s premiership. Initially introduced in Section 145B (on inducements related to collective bargaining) to preserve by its stringency some scope for contractual flexibility, it was extended to Section 146 for consistency despite the obvious fact that its rationale did not extend to the latter. Developed as a test applicable to a range of provisions (Sections 145A, 145B and 146), the ‘sole or main purpose’ test tightened the previous language, which merely required a purpose of deterring, preventing or penalising for trade union activities in Employment Protection Act 1975 (Section 53(1)). Section 236A further mainstreams this restrictive formulation. This represents an almost paradigmatic case of path dependence disguised as ‘consistency’ and ‘familiarity’. The legislator reaches uncritically and almost reflexively for ready-made statutory formulations, perhaps out of convenience, without systematically considering their suitability in different contexts.

Before further accounting for the restrictive nature of the test, it is important to acknowledge several countervailing points. The first concerns the burden of proof, placed on employers. Once a worker establishes being subject to a detriment, the employer must demonstrate that the sole or main purpose was not that of deterring, preventing, or penalising industrial action participation. From this fact, one could submit that the purposive test is a fair counterweight to the evidentiary burden imposed on the employer, as part of the fair balancing struck by the provision. Second, it should be noted that the strict construction of the purposive test was regarded by the Government as a safeguard against the concern raised by businesses about the prospect of ‘vexatious’ and ‘speculative claims’ brought by ‘bad faith’ workers. Indeed, the Government’s response paper made an explicit reference to the test when addressing business concerns about litigation (DBT 2026c, p. 28).

While these concerns may be somewhat overstated, particularly given workers’ general aversion to individual litigation due to financial and psychological barriers among others, they are not devoid of any merit. On balance, however, they should not obscure the operation of the test as an overly restrictive filter, liable to undermine the gap-filling function of the universal prohibition. It shifts much of the legal uncertainty, which to an extent is inherent in any construction of the link, onto workers. This occurs for at least three main reasons.

First, the test effectively filters out cases in which the retaliatory purpose is merely one among a broader matrix of purposes (mixed-purpose cases). Consider, for example, an employer deciding which sales assistant should receive a training opportunity that is regarded as necessary for promotion on the basis of a sophisticated qualitative matrix comprising four equally weighted criteria: disciplinary record; number of customer complaints; sales performance; and days of participation in the most recent industrial action. In this scenario, the employer can escape Section 236A liability by demonstrating that industrial action participation was not its sole or main purpose for the detriment as evidenced by the equal weighting of the four criteria. The fact that industrial action participation made a clear ‘material contribution’ to the detriment would not be sufficient to pull the trigger.

Relatedly, Section 236A cannot capture ‘last straw’ cases: instances where participation in industrial action carries on its own a minor weight in the employer’s decision-making but its cumulative effect proves decisive in tipping the balance in favour of imposing the detriment. For example, consider an employer who becomes increasingly frustrated with an employee’s persistent lateness at work but keeps postponing disciplinary action for no obvious reason other than sheer forgetfulness. When the employee subsequently informs them that they would also be absent because of participation in a strike, the employer recalls the previous infractions, concludes that ‘enough is enough’ and decides to impose disciplinary action. This case would be prohibited by a ‘but for’ test, since no detriment would have occurred if the worker did not participate in industrial action, but is unlikely to be caught by the current formulation of Section 236A.

Besides these problems, the test also places significant evidentiary burdens on workers. In many cases, even establishing the employer’s purpose may not be as straightforward, not least due to difficulties in accessing the relevant information necessary for preparing an effective case and assessing its chances of success. The employer’s decision-making typically involves various decision-makers, often with varying degrees of awareness as to the retaliatory aims and inputs, and they may actively seek to conceal their retaliatory motive from workers. A particularly complex issue concerns penalisation for misconduct occurring in the ‘context’ of the strike but not directly because of strike participation. For instance, a worker disciplined for bringing the ‘company into disrepute’ by speaking out to the press and disclosing confidential information, acts undertaken to attract public support for the industrial action. This was the factual context of Mercer. But no decision as to whether the facts satisfied the purposive test was taken as the case proceeded on assumed facts. Obviously, the employer could insist that its purpose is to protect reputation and any effect of deterring industrial action was merely incidental and ancillary. The presence of the sole or main purpose test makes such an argument easier to sustain.

Second, it bears emphasis that the nature of the purposive requirement inquiry is ultimately employer centric in contrast to the detriment one which is focused on the perception of a reasonable worker. Crucially, it does not take into account the actual effect of the detriment on workers’ strike participation but looks instead at the intended effect by the employer. This requires a highly subjective investigation into the employer’s mental state, which can be an opaque and elusive undertaking.

A practical question thus appears: what about disproportionate sanctions? By way of an example, consider the case of an employer who has legitimate grounds for disciplining a worker due to poor performance, but where the sanction becomes disproportionate due to strike participation. Suppose, for instance, that a worker found to have breached a minor rule of the workplace handbook receives a final warning due to strike participation instead of an oral warning. In this case, the Court should assess the employer’s retaliatory purpose with reference to the disproportionality of the sanction. It is this disproportionality that should be viewed as constituting the detriment, although this can often be difficult for workers to establish in practice.

Third, it should be mentioned that employers and business associations voiced concerns regarding the ‘administrative burden of evidencing decision-making’ (DBT 2026c, p. 10)  as a result of universal prohibition. Their concern was that the broad scope of the prohibition would require employers to justify a wider range of decisions through the purposive inquiry.  For this, they would need to take steps to preserve evidence for decision-making during or around industrial action which is at risk of qualifying as a detriment.  But here the benefits, not just for the worker but more broadly for employment relations, seem to outweigh any burden on employers.  At the very least, it can nudge businesses to be mindful of the importance of justifying decisions during or around industrial action and confirming that they are not linked in a pernicious way to the industrial action. In turn this could also contribute to fostering better employment relations that promote a culture of justification, transparency and accountability.

On balance, the purposive requirement presents a major gap in the scope of protection. However, its overly restrictive function primarily stems from its design rather than clarity. Thus, while many respondents called for detailed guidance on its meaning, ‘including worked examples of what would and would not fall within scope’ (DBT 2026c, p. 25), a caution against inflating expectations is warranted. The context-specific nature of the purposive stage of Section 236A renders it less susceptible to a generic, ex ante reduction to clear-cut examples thus limiting what a guidance can realistically offer.

It is unfortunate that the almost habitual replications of pre-existing formulations, detached from their original context, preclude a systematic consideration of the merits of more appropriate alternative formulations. For example, the ‘because of’ test employed in the Equality Act 2010 (see Section 13) for establishing the link between a protected characteristic and discrimination seems a more apt candidate for a better-balanced model of protection. If adopted, the detriment would need to be imposed merely ‘because of’ strike participation to be prohibited. While a degree of causation would still be required, it would fall short of the stringency of the sole or main reason test. In the context of anti-discrimination case-law, Courts have interpreted it as not requiring the protected characteristic to be the ‘sole’ grounds but merely to have a ‘significant influence on the outcome’ (see Nagarajan v London Regional Transport [2000] 1 AC 501, LJ Nicholls). Although this case-law developing the ‘significant influence’ test concerned the pre-2010 statutory language (‘on the ground of’), it is generally accepted that it also governs the interpretation of the ‘because of’ requirement (as also reflected in the Government’s explanatory notes confirming that the intention was not to alter the ‘legal meaning’ of the previous test but merely to make it more accessible for ordinary users; see Section 13, para. 61).

4. Disproportionate Wage Deductions as Detriments: A Missed Opportunity for Clarity

In reality, wage deductions are among the most potent deterrents against taking part in industrial action. The reason is straightforward. Workers qua humans typically depend on wages for their own subsistence as well as that of their dependants. Capital has the luxury of not sharing such concerns.

Law of course permits deductions for industrial action. Succinctly captured, it enshrines the principle of ‘no work, no pay’ (see DBT 2026c, p.9). With regard to legislating on detriments, the consensus on the permissibility of wage deductions can perform a strategic role. This is to support an argument for the alleged absurdity of those defending a universal prohibition of detriments. Since wage deductions by common accord are a detriment yet permitted, the reasoning goes that the universalist position cannot hold. The legal response is familiar. Law carves a singular exception by not deeming them as detriments at all – and thereby obviating the need to apply the ‘sole or main purpose’ test – which allows it to maintain ‘universality’, perhaps through a feat of slight legal alchemy.

Legal reality, however, does not neatly fit the ‘no work, no pay’ principle. The latter cannot settle what happens in cases of an  action short of a strike involving ‘less work, but much less pay’. Or when workers withdrew their good will, meaning that they perform their ‘work’ according to the contract but not anything beyond. This raises the issue of disproportionate deductions. The common law position of course is not crystal clear. But it seems a fair characterisation to say that it allows an effective partial lock-out by the employer against workers taking part in industrial action by refusing partial performance as long as this is communicated to workers (see Miles v Wakefield [1987] and Mead 2022). The marking and assessment boycott undertaken by UK universities offered a particularly illustrative case-study (Mead 2022). Universities threatened to (or imposed) 100% deductions even if the work not performed (i.e marking) amounted to a small part of the overall contractual duties (teaching as a whole typically amounts to 40% of contractual duties for most teaching and research positions in UK universities). Since these deductions almost invariably can be viewed as clearly aimed at penalising or preventing/deterring industrial action participation, the question of whether they qualify as detriments is likely to be determinative of their overall legality.

Section 236A provided an opportunity for addressing the gap by explicitly excluding disproportionate detriments from the universal prohibition. However, the draft regulations seemed to take another route.

In particular, they contain the following sentence:

‘Nothing in these Regulations affects the common law rules enabling the deduction of pay on account of a worker having taken part in protected industrial action(a)’ (Draft Statutory Regulations, 2026 Section 4).

How to read this sentence? One interpretation is that Section 4 confirms that the regulations do not affect the common law position, thereby seeking to shield it from any attempts to infer a statutory intention to the contrary. This aligns with the Explanatory Notes, which state ‘that the common law rules which allow an employer to deduct pay from a worker for having taken part in protected industrial action are not affected by these Regulations’ (Draft Statutory Regulations, 2026, Explanatory Note).

But the most interesting question is the reverse: is the question of whether wage deductions constitute a detriment under Section 236A to be fully governed by (or delegated to) common law? Granted, these are not wholly unrelated questions. But they are still distinct. While the draft regulations did not address this question, they are more restrained than the consultation document that seems to go further. This consultation document cast the Government’s intention in much broader terms, as ‘to prevent an employer from acting in accordance with the common law to deduct pay from a worker who takes strike or other industrial action, or to subject an employer to a complaint for detriment under section 236A for making such a deduction’ (DBT 2026c, p. 29). The question of course now turns to what is ‘such’ a deduction? Is it a proportionate deduction or a deduction in general?

Quite understandably, the Government’s evasiveness may reflect a reluctance to be drawn into a complex legal quagmire, potentially exposing suppressed fault lines between common law and human rights law. Nevertheless, it feels like a missed opportunity.  It would be a welcome and crucial clarification if the regulations expressly stated that proportionate wage deductions are excluded from the definition of the detriment. This would also enable the alignment of the exclusion with human rights, rather than leaving it hostage to the obscure vagaries of common law. It is not inconceivable of course that common law can evolve to accommodate a prohibition on disproportionate wages through an implied duty to respect human rights. But such a development is quite unlikely at present. Alternatively, like the example of disproportionate sanctions mentioned above, Courts could develop a doctrine based on the ‘disproportionality’ of the deductions as a detriment. But this is far from assured. In this context, a legislative exclusion of disproportionate deductions would go some way towards addressing this gap, promoting legal certainty and providing some legal protection against the abuse of wage deductions for partial performance used as a device of retaliation by employers. And the issue may well attract early litigation under Section 236A, forcing the Government to abandon its evasiveness by confronting this quagmire anyway. In this sense, disproportionate deductions are Section 236A’s unfinished business.

5. Mind the Enforcement Gap: A Weak Eco-System

A major limitation that can severely undermine the effectiveness of Section 236A and the universal prohibition of detriments is the presence of a weak ‘enforcement eco-system’ (Countouris 2024). Labour rights are of little value in the absence of a realistic prospect of enforcement and the provision of an effective and deterrent remedy. And often employers ‘price in’ these prospects in their decisions, especially when only monetary remedies are provided (for the case of P&O Ferries see Bogg 2025 and Katsaroumpas 2024).

Enforcement represents of course a common challenge for labour law rights, considering the typical asymmetries against workers in terms of resources, power and information. But when it comes to detriments for taking part in industrial action, the nature of the harm accentuates the barriers. This is for at least two reasons. Unlike dismissals, the employment relationship in detriment cases typically continues or at least the worker intends for it to do so. As a result, workers may be more reluctant to bring a claim for fear of losing their jobs. Additionally, detriments may be harder to detect as employers may seek to conceal them by invoking alternative motivations. Consequently, a worker may not even be aware that they suffered a detriment for industrial action participation.

The ETUI policy brief on the topic found that most countries go beyond monetary remedies and a purely individualistic model of litigation (Katsaroumpas et al 2025). Available remedies extend to the issuing of injunctions, annulment of unlawful detriments and treating transgressions (as in Portugal) as ‘serious administrative offences’ (see Katsaroumpas et al 2025). This also reflects a perception of detriments as a public wrong affecting the exercise of a human right rather than a private matter between private persons. Equally important is the ability of unions to bring claims on behalf of their members or in their own name, which could address, as a complementary mechanism, workers’ reluctance to pursue litigation individually.

In its response, the Government identified ‘stronger enforcement’ as a major theme. In its response paper, it highlighted calls for ‘the need to strengthen enforcement and remedies beyond what is currently being proposed’ (DBT, 2026c p. 25). And it also referred to proposals to ‘expanding enforcement mechanisms to allow trade unions to bring claims on behalf of workers or groups of workers and introducing stronger remedies, such as injunctions, annulment of unlawful detriments, and financial penalties, with some European jurisdictions as modelscl’ (DBT 2026c, p. 26). Yet in the section addressing ‘other issues’, the Government confined its response discussion to the role of the ‘sole or main purpose test’ as a filter against the fear of ‘vexatious’ claims. Its relative silence on enforcement is, only to some extent, understandable. Neither the consultation nor the forthcoming regulations may be the most appropriate fora for considering these broader issues. Nevertheless, a legislative response in this area is essential if the Government’s objective of ‘full protection’ of workers against detriments is to be realised in practice.

6. Conclusion

By any standard, the Government’s consultation response together with the forthcoming regulations represents a laudable step that should be cautiously celebrated. It is a great place to be in, to consider a well-informed policy intervention that seeks to close, rather than extend, the gap with human rights and standard comparative practice.

If we are to hazard an attempt to situate the present moment within the broader long durée of UK strike law, two features seem to stand out. First, Section 236A (together with the regulations) can be viewed as almost the terminal point of a long journey away from the ‘collective laissez-faire’ conception of sanctions for industrial action as a permissible form of ‘collateral damage’ in industrial conflict. Almost half a century ago, a judge observed that the law ‘enables him [the employer] in those circumstances, if he cannot carry on the business without a labour force, to dismiss the labour force on strike; to take on another labour force without the stigma of its being an unfair dismissal’ (Heath v. J. F. Longman (Meat Salesmen) Ltd [1973] ICR 407, at 410).

Since the Employment Protection (Consolidation) Act 1978 which prohibited only selective dismissals for participation in industrial action and the introduction in the 1970s of protections against dismissal and actions short of dismissal for activities and membership, the legal regime has undergone numerous reforms and reconfigurations in response to various legal and ideological twists and turns. It is quite striking that an automatic protection against unfair dismissal for taking part in industrial action was established as late as the Employment Relations Act 1999 (TULRCA 1992, Section 238). Yet most legislative interventions have been episodic and reactive, more recently in the form of responding to specific Article 11 judgments.

Second, UK law should reckon with the following reality. Despite the formal absence of a positive right to strike in UK domestic law, Article 11 is increasingly performing a functionally equivalent role (through the Human Rights Act 1998). Not only negatively as a basis for statutory incompatibility, but also positively as shaping the parameters within which legislation is drafted.  The Mercer litigation and judgment seemed crucial. Counterfactuals are of course always speculative. But would Section 236A have been proposed in the absence of this judgment and the Declaration of Incompatibility? Possibly, but not certainly. The Government, quite surprisingly given that the statutory intervention is a direct response to Mercer, did not build the case entirely for universal prohibition of detriments on Article 11 and Mercer. However, it is plausible to speculate that business resistance – as also refracted within the balance of opinion within the Government – would have been stronger in the absence of Mercer. In those circumstances, a closed list might well have appeared to offer a fair-sided compromise. UK labour law thus already bears witness to law-making in the shadow of a positive right to strike.

Finally, a procedural observation is in order. Episodic reactive intervention, responding to specific events or judgments, has its own virtues. It can reflect pragmatism, remain attentive to the bounds of contemporary political feasibility and fit neatly into an incremental, step-by-step and consensual approach to addressing human rights gaps. One may wonder, however, whether a more holistic review of the law governing action and labour relations more broadly is now overdue. History and shifting ideological currents (most notably neo-liberalism) have placed a range of obstacles in the path of an effective right to strike (including the ‘sole or main’ purpose test). Some have been thrown deliberately, others inadvertently as unintended consequences (such as the lack of protection against detriments for industrial action participation). The entire picture risks being occluded from view when in each reform policymakers adopt a narrow, kaleidoscopic view of the edifice as they focus on one part. There thus seems to be a strong case today for a comprehensive review undertaken by a Commission of Experts in the tradition of the Donovan Commission, informed by rigorous comparative and human rights analysis. Granted, such an exercise would require a greater investment of work, energy and time upfront. Yet it could yield significant dividends further down the line in terms of addressing protective gaps. This is because it could offer an opportunity to ensure more robust protection by identifying, evaluating and addressing systematically the various limitations, which otherwise are not only allowed to survive but to be mainstreamed on the grounds of consistency or familiarity.

To conclude, the adoption of a universal prohibition on balance deserves proper commendation. It represents a significant step in closing the major gap flagged in Mercer. Yet the task remains incomplete. A second round of legislative intervention is warranted in light of remaining gaps. Addressing the latter would help ensure that the Government’s stated aim of granting ‘full protection’ against detriments to workers on strike becomes a reality for workers. It would also firmly excise from UK strike law any remnants of the outdated conception of individual detriments as legitimate deterrents in industrial conflict.

Acknowledgments: I would like to specially thank Alan Bogg, Kalina Arabadjieva and Hugh Collins for their excellent comments on earlier drafts and Simon Collerton for all his editorial support. The usual disclaimer applies. I am also grateful to Rudolf Buschmann, Sergio Canalda Criado, Konstantina Chatzilaou, Filip Dorssemont, Andrea Iossa, Tena Konjevic, Vincenzo Pietrogiovanni and Ana Teresa Ribeiro for our co-authored ETUI policy brief ‘Tackling hidden retaliation for strike participation: Examples of legal protection from detriments short of dismissal’, on whose comparative findings the blog draws.

Suggested citation: I Katasroumpas, ‘Legislating on Detriments for Taking Part in Industrial Action: Reflections on the Government’s Response to Consultation’ UK Labour Law Blog, 7 September 2026, available at https://uklabourlawblog.com)