SENDING an email, only to realise it has been misdirected or includes sensitive, superfluous material, is the sort of anxiety-inducing administrative mishap with which most people can identify. But few such errors have consequences as calamitous as those that occurred when an official mistakenly attached to an email an enormous dataset containing the details of Afghans who, having assisted the UK Government during its military presence in Afghanistan, had applied to settle in the UK. The resulting possibility of the dataset’s ending up in the hands of Afghanistan’s Taliban regime endangered thousands of lives, necessitating an emergency relocation scheme that may end up costing several billion pounds.

Amid concern that publicity would heighten the risks created by the data breach, the Ministry of Defence, in September 2023, obtained from Robin Knowles J. not only the injunction, restraining disclosure of the data breach, it had requested, but an apparently unprecedented superinjunction contra mundum, imposing a worldwide prohibition on disclosure of the injunction’s existence. In a series of judgments, Chamberlain J. reviewed the superinjunction. Having concluded in November 2023 (Secretary of State for Defence v Persons Unknown [2023] EWHC 2999 (KB)) and February 2024 (Ministry of Defence v Global Media and Entertainment Ltd. [2024] EWHC 312 (KB)) that it should remain in place, he decided in May 2024 that it should be discharged (Ministry of Defence v Global Media and Entertainment Ltd. [2024] EWHC 1220 (KB)). The Court of Appeal ([2024] EWCA Civ 838), however, overruled him three months later and it was not until 2025 that the superinjunction was discharged and replaced with an injunction restraining disclosure of the content of the dataset as distinct from the fact of the data breach (Ministry of Defence v Global Media and Entertainment Ltd. [2025] EWHC 1806 (Admin)).

This note considers two key aspects of this series of judgments: the respective, and ultimately contrasting, approaches of Chamberlain J. and the Court of Appeal to scrutiny of the Government’s justification for maintaining the superinjunction; and the role played by the principle of parliamentary accountability, to which the Supreme Court ascribed legal force in R. (Miller) v Prime Minister [2019] UKSC 41, [2020] A.C. 373 (“Miller II”).

In successive hearings, the Government argued the superinjunction’s continuation was needed to prevent the Taliban from learning of the data breach and obtaining the dataset, thus providing time for the implementation of the emergency relocation scheme. Chamberlain J. set out the principles governing the assessment of that justification in his November 2023 judgment (at [35]). While acknowledging that the Government’s “predictive judgment … about the extent of any risk to life is entitled to respect”, he emphasised that it was “for the court, not the executive, to decide where the balance of public and private interests falls”; that the court needed to bear in mind the possibility that the superinjunction might endanger, as well as reduce the risk to, life (e.g. concealing the fact of the data breach might prevent those outwith the scope of the emergency relocation scheme from advocating for inclusion in it); and that the public interests in play included those “in open justice and in the transparency of public decision-making”. Such considerations, he said (at [36]–[38]), had “special significance and weight” in the present context, given the likelihood of “suspicion that the court’s processes are being used for the purposes of censorship”, which would be “corrosive of the public’s trust in Government”, and the superinjunction’s evisceration of democratic processes.

Although this case did not involve judicial review of discretionary power, the principles governing scrutiny of and deference to executive judgment in that context – which are the subject of extensive case law, lucidly summarised and synthesised by Chamberlain J. in KP v Secretary of State for Foreign, Commonwealth and Development Affairs [2025] EWHC 370 (Admin) – rightly have much in common with the principles articulated in this case. In particular, the importance of the constitutional norms impacted by the superinjunction and the considerable extent of that impact counsel in favour of close scrutiny. Applying such an approach and noting that by May 2024 the evidential position had stabilised – meaning that continuation of the superinjunction would logically imply the propriety of keeping it in place for a substantial additional period of time – Chamberlain J. resolved (May 2024 judgment, [28]) that “the nettle must … be grasped now”. He noted (at [39]) that there was a “significant possibility” that the Taliban had by then learned of the dataset’s existence, creating a risk for thousands of individuals who would remain in ignorance of the data breach and would be prevented by the continuation of the superinjunction from seeking to mitigate the possible effects of the breach. He also observed that, were the superinjunction to remain in place, those not being considered for emergency relocation would be denied any possibility of challenging their exclusion from the scheme. Moreover, after eight months, it had become “fundamentally objectionable for decisions that affect the lives and safety of thousands of human beings, and involve the commitment of billions of pounds of public money, to be taken in circumstances where they are completely insulated from public debate” (at [48]). The balance had shifted: the extent of any protective effect of the superinjunction was weakening, while the constitutional and democratic corrosion occasioned by the impossibility of public or parliamentary scrutiny was compounding as time passed.

Overruling Chamberlain J., the Court of Appeal was concerned (at [61]) that discharging the injunction would “turn what was a real possibility” of the Taliban’s having obtained the dataset “into a virtual certainty”. This, however, overlooked the risks – in terms of denying opportunities for mitigation to those who might already be in danger – of maintaining the superinjunction. More generally, the Court of Appeal said (at [73]) Chamberlain J. “appears to have thought that the simple fact that the super-injunction had been in existence for an unprecedented amount of time was a reason to think that it was no longer necessary”. It is, however, difficult to see (and the Court of Appeal failed to identify) any basis in Chamberlain J.’s carefully reasoned May 2024 judgment for that characterisation of it. The real difference between the approaches of Chamberlain J. in May 2024 and the Court of Appeal lies in their respective preparedness to form an independent view about the balance of public and private interests. While the Court of Appeal’s judgment did not lack rhetorical flourishes acknowledging the constitutional implications of maintaining the superinjunction and while it did not demur from the principles articulated by Chamberlain J. in his November 2023 judgment concerning the need for the courts to form their own independent view, there is limited evidence of the Court of Appeal’s willingness actually to do that.

When Chamberlain J. finally discharged the superinjunction in July 2025, he did so in the light of a government-commissioned review’s conclusion that the Taliban’s acquisition of the dataset would have much more limited consequences than had originally been assumed because so much other information was already available to the Taliban. The judge noted (at [33]) that the assessments made in the review were “very different from those on which the super-injunction was … granted” and that such difference could only partly be attributed to the passage of time. This raises the question whether the superinjunction was ever actually necessary. On this point, Chamberlain J. observed (at [33]), with notable restraint, that it will be “for others to consider whether lessons can be learned from the way the initial assessments in this case were prepared and whether the courts were, or are generally, right to accord such weight to assessments of this kind”.

As well as raising questions about the appropriate level of judicial scrutiny of the justifications proffered by the Government, this case prompts reflection upon the place of parliamentary accountability within the constitutional order and of the extent to which that value ought to inform judicial decision-making. It certainly featured prominently in Chamberlain J.’s several judgments, in which he noted that the effect of the superinjunction was to create a “scrutiny vacuum” (November 2023 judgment, [39]) by “completely shutting down the ordinary mechanisms of accountability which operate in a democracy” (July 2025 judgment, at [10]). Chamberlain J. recognised that, thanks to Article IX of the Bill of Rights, no superinjunction that sought to restrain proceedings in Parliament “would be constitutional or lawful”. But he also observed that the practical effect of the then-extant superinjunction (which did not purport formally to extend to parliamentary proceedings) was to preclude all scrutiny given that “MPs and peers cannot ask questions about something they do not know about” (November 2023 judgment, at [16]).

While it might once have been tenable to argue that such matters are legally irrelevant, on the ground that the accountability of the executive to Parliament is firmly part of the political constitution, the position today is complicated by the Supreme Court’s judgment in Miller II, in which (at [46]) it endorsed the view advanced by Lord Carnwath in R. (Miller) v Secretary of State for the Exiting the European Union [2017] UKSC 5, [2018] A.C. 61, at [249] that the principle of parliamentary accountability is “[n]o less fundamental to our constitution” than parliamentary sovereignty. The Supreme Court in Miller II went on to hold that parliamentary accountability forms a legal limit on the prerogative power to prorogue Parliament. It is surprising that, given its framing of parliamentary accountability as a legal principle, Miller II was never mentioned in any of the several Afghan superinjunction judgments. And it is particularly surprising that the Court of Appeal appeared to adopt a wholly instrumental view of parliamentary accountability, holding that the possibility of parliamentary scrutiny was not a good reason to discharge the superinjunction because, in the court’s view, such scrutiny would have been unlikely to improve the position of relevant individuals. This contrasts with the much broader view adopted by the Supreme Court in Miller II: against the background of a five-week prorogation that would have prevented Parliament from executing its constitutional functions, the court observed (at [48]) that “the longer Parliament stands prorogued, the greater the risk that responsible government may be replaced by unaccountable government: the antithesis of the democratic model”. Such considerations plainly apply with even greater force to a superinjunction that had the effect of preventing all parliamentary accountability in respect of a hugely consequential administrative failure for nearly two years. It follows that the Court of Appeal’s instrumental conception of parliamentary accountability is a highly impoverished one that contrasts markedly with the Supreme Court’s position in Miller II.

It would be easy to conclude that no relief should ever have been granted now that we know from the Government’s own review that the dataset “is unlikely to significantly shift Taliban understanding of individuals who may be of interest to them” – a conclusion that, as Chamberlain J. put it in his July 2025 judgment (at [26]), “fundamentally undermine[s] the evidential basis” on which he originally continued the superinjunction in November 2023. But of course, the information available to the courts in 2023 was very different and the case for the superinjunction seemed pressing at that juncture. The real concern that arises from this series of judgments relates not to the initial willingness of the Administrative Court to grant the superinjunction, but to the posture adopted by the Court of Appeal almost a year later. Its limited preparedness to form an independent judgment about where the balance of private and public interests fell and its narrow, instrumental view of parliamentary accountability combined to shield the Government’s position not only from all parliamentary scrutiny but from the level of judicial scrutiny that was plainly warranted by the superinjunction’s extraordinary constitutional implications. It is trite to observe that much of this sorry episode takes on a different complexion when viewed with the benefit of hindsight. But no hindsight is needed to discern the errors into which the Court of Appeal fell. It is to be hoped that they will not be repeated.