Collateral challenges – what is their place in the contemporary administrative justice landscape?
Lee Marsons and Yseult Marique (University of Essex)
With the Independent Review of Administrative Law (IRAL), judicial review is very much on the political and legal radar. Not that it ever left, of course. As Joe Tomlinson has argued, despite several other avenues long being the dominant means of challenging unlawful administrative acts and despite these avenues having their own significant problems, these receive far less attention in the academic literature than judicial review. In particular, these alternatives include administrative review, complaints to ombuds, and statutory appeals to tribunals. This post relates to one of the most under-studied of those under-studied options, that of collateral challenges. This is when, without pursuing a judicial review and the associated remedies in the High Court, an individual invokes the illegality of an administrative act as a defence in criminal proceedings, or to resist a decision in civil proceedings. This arises from the murkier, even non-existent, public-private divide in English law, where public law matters can be raised in otherwise private law proceedings.
The classic modern authority is Boddington v British Transport Police  UKHL 13, where the House of Lords held that the claimant was permitted to raise the illegality of a certain byelaw as a defence in his magistrates’ court trial. This was subject to a parliamentary power to limit collateral challenges expressly or by necessary implication through statute. A more recent non-criminal example was decided by the Supreme Court in May 2020, called Dill v Secretary of State for Housing  UKSC 20. This related to whether the claimant could resist a local authority decision to register two urns as ‘listed buildings’ via a collateral challenge with the planning inspector, rather than via a judicial review. The Justices unanimously decided that the claimant could.
The spectre of collateral challenge also haunted the Lord Chief Justice at  in R (Dolan) v Secretary of State for Health  EWCA Civ 1605, which concerned the legality of the initial lockdown in England:
We have come to the conclusion that it would serve the public interest if this Court itself were to decide that issue now rather than leave it, for example, to be raised potentially by way of defence in criminal proceedings in the Magistrates’ Court and no doubt on appeal from there to the higher courts.
It is fairly common for the senior courts to find that collateral challenge has been excluded by necessary implication: Beadle v Her Majesty’s Revenue and Customs  EWCA Civ 562; R (London Borough of Camden) v Parking Adjudicator  EWHC 295 (Admin); and R (Noble Organisations) v Thanet Council  EWCA Civ 782. However, this is not inevitable: Clockfair Ltd v Sandwell Metropolitan Borough Council  EWHC 1857 (Admin); Earthline v Secretary of State for Transport  EWCA Civ 1599; Dilieto v Ealing London Borough Council  QB 381; Newbury v Secretary of State for Environment  AC 578. Therefore, especially in light of Dill and Dolan, we think that there is scope for a broader conversation about the place that collateral challenges have in the wider contemporary landscape of administrative justice. This post is an attempt to encourage that conversation.
The collateral challenge black-box
In most public law textbooks, collateral challenges are relegated to half a page and the obligatory reference to Boddington. There are at least four reasons for this. One is that, in contrast to the relative transparency of senior court judgments, there is a ‘data gap’ on the reasons why decisions are made in the lower courts. As the Lammy Review noted, the exact reasons for individual decisions by magistrates can be highly obscure and are regularly not published. It can be even more difficult to publicly access the reasons for most decisions in the county courts. Therefore, the number of decisions in the lower courts based on a collateral challenge is difficult to estimate.
Two is that collateral challenges can occur entirely outside the courts. An obvious example is Dill, where a planning inspector could consider a collateral attack on vires in the process of a statutory appeal. For administrative lawyers more used to scouring senior court decisions, these may be missed. Three is that, following a successful collateral challenge, a public body may simply withdraw the decision in issue. This is what happened in Dill (thank you to Richard Harwood QC, leading counsel in the case, for letting us know this).
The fourth is more substantive and concerns the tendency of lawyers to become stuck in disciplinary silos. Especially in light of the possibly non-existent public-private divide, collateral challenge sits messily at the frontier between apparently distinct areas of law – our initial research indicates that, at least in reported cases, it is most often invoked in case stated appeals from the magistrates’ court, as well as in planning, taxation, licensing, and parking matters. Sometimes, it can be unclear that these are even issues related to administrative law. As Richard Harwood QC has commented, there is a failure to make connections between administrative law and other discrete areas despite the necessary interconnections.
Consequently, collateral challenges are something of a data black-box. The precise numbers, their immediate results, and their broader consequences are, at present, guesswork deducible from the accessible senior court references to them.
The importance of further research
While there was considerable academic commentary on collateral challenges post-Boddington, such as a piece by Professor Forsyth and a piece by Sir David Keene in Judicial Review in 1999, the contemporary commentary is much more limited. There has been some consideration of the situation in Australia by Jules O’Donnell in 2019 and blog references by Paul Daly to Canadian law (here and here), but nothing systematic specifically on English law. Though there are overlaps between these jurisdictions (not least because both Australia and Canada rely on Boddington), there are equally different statutory appeal rights, procedures for judicial review, alternatives to judicial review, costs regimes, and other considerations that may distinguish them in concrete ways. Therefore, we think that collateral challenge in English law is ripe for systemic consideration across the areas of law where it arises, with possible comparative attention across the common law world too.
We also wonder whether some of the justifications for collateral challenge need to be revisited and revised. For instance, in R v Reading Crown Court ex p. Hutchinson  1 QB 384, Lloyd J. noted the importance of collateral challenge on the basis that:
Coming to London to the High Court is inconvenient and expensive. Byelaws are generally local laws which have been made for local people to do with local concerns. Magistrates’ courts are local courts and there is one in every town of any size in England. The cost of proceedings in a magistrates’ court are far less than in the High Court. I believe this egalitarian aspect of seeking recourse to the law in a magistrates’ court to be an important sign of the availability of justice for all.
These days, of course, the High Court sits outside of London and with so-called ‘court modernisation’ (aka court closures) there may not be a magistrates’ court in every town. In addition, while legal aid has broadly been retained for judicial review, it is largely absent from civil private law proceedings and is means-tested in criminal courts. As such, Lloyd J.’s justifications based on accessibility and costs may have been of their time. Are revised pragmatic justifications needed for collateral challenge today?
Beyond this, we think that the debate on collateral challenge must be directly linked not just to judicial review but also to the growth of alternative systems of administrative redress, which – as mentioned in the introduction – now make up most of the scene. For instance, contemporary administrative justice scholarship has highlighted the notion of ombudsprudence, that is, a unique body of decisions and norms produced by ombuds. With cases such as Dill, is there the potential for a unique inspectorprudence – decisions by the planning inspectorate about local authority approaches to planning legislation – to be developed and what would the consequences be? There are no doubt other connections with administrative justice to be explored too.
Hearing practical experiences
For all these reasons, we would like to encourage discussions between researchers, on the one hand, and practitioners who have engaged in collateral challenges, on the other hand. Indeed, initial asking around has indicated that there are a reasonable number of practitioners with first-hand experience.
Critical initial questions might include: In practical terms, does the issue of collateral challenge arise that often or is the preference to leave a vires issue to a senior court which can order coercive relief? Particularly in light of the Simms principle of legality, are courts too ready to find that a statute has excluded collateral challenge by necessary implication? Does the practical value of collateral challenge differ depending on the area of law? Has the practical value changed over time, with an increasing number of locations for the Administrative Court and a decreasing number of local courts?
Are claimants who have doubts about the legality of an administrative decision dissuaded from challenging those decisions via collateral attack due to the costs of the litigation outweighing, say, the fine in issue? In an administrative world where there are a range of tribunals, ombuds, inspectorates, and internal reviewers, and where legal aid has been retained for judicial review, is collateral challenge needed as a residual option in its current form? Or does it need to be modernised to take into account its specific interactions with these various administrative bodies and processes?
Moreover, as Lord Carnwath noted at  in Dill, sometimes the public body hearing the collateral challenge might be in a better position than the Administrative Court to make decisions concerning vires, especially where those issues are strongly interrelated with factual considerations. Particularly from the perspective of practitioners who have pursued these issues, in what circumstances might a public body or lower court be in a better position to determine a vires issue than the High Court? For instance, is it important that a lower court might more readily hear oral evidence than the Administrative Court in a judicial review?
Initially, it would be useful to produce a collective repository via UKAJI of collateral challenges, both reported and not, noting their legal outcomes, broader consequences, statutory schemes, and practice areas. This might become a useful resource for scholars and practitioners alike. In time, this might lead to suggestions for reform proposals. Might, for instance, statutory intervention in this area be desirable, such as the possibility of an emergency reference to a senior court to resolve a vires issue (cf. the devolution references to the Supreme Court)? Should collateral challenges be subject to a statutory time limit, particularly where other individuals have relied on the public decision? Given the data gap, might an obligation on public bodies to publicly declare collateral challenges and their outcomes be helpful to encourage greater transparency and consistency? Indeed, in a time of online databases and digital administrative decision-making, is it not possible that collateral challenges should be publicly recorded online, encouraging a ‘feedback loop’ in the relevant administrative infrastructure?
We have no pre-existing preferences on these questions but we do think that they are worth asking and thinking about. As Dill and Dolan have demonstrated, the issue of collateral challenge has not vanished entirely from the administrative law scene and the situation across areas of law has been largely unstudied as of late. Anyone interested in engaging with this discussion or providing cases for UKAJI’s collation, should contact Lee Marsons on email@example.com and/or Yseult Marique on firstname.lastname@example.org.
Our thanks to Richard Harwood QC for providing material on Dill.