Introduction
The relationship between the state and its citizens in the United Kingdom is underpinned by principles of accountability and transparency. A key component of this relationship is the common law duty of candour, which requires public authorities to be open and honest, particularly when their actions are subject to legal scrutiny. This duty serves to level the playing field between the individual and the state, facilitate the rule of law, and maintain public confidence. However, the application of this duty to national security bodies, such as the security and intelligence agencies, presents a significant challenge. These organisations operate in a sphere where secrecy is often considered essential for their effectiveness and for the safety of their personnel. This creates a direct tension between the public’s right to know and the state's perceived need for secrecy.
Recent debates, particularly those surrounding the proposed statutory ‘Hillsborough Law’, have brought this conflict into sharp focus, questioning whether national security imperatives can ever justify a departure from the fundamental duty of candour. This essay will argue that while the operational needs of national security bodies are a powerful consideration, they should not be granted a blanket exemption from the duty of candour. A complete exemption would risk creating a zone of impunity, undermining accountability and frustrating the search for truth, especially for bereaved families affected by state action or inaction. Instead, the law should continue to manage this tension through tailored procedural mechanisms, such as Public Interest Immunity and Closed Material Procedures, which are subject to judicial oversight. This approach, while imperfect, allows for a balancing of interests rather than the complete sacrifice of transparency at the altar of national security.
The Duty of Candour in English Public Law
The duty of candour is a well-established, albeit uncodified, principle of UK public law. It is not a freestanding duty that can be enforced in the abstract, but rather a standard of conduct expected from public bodies, particularly in the context of legal proceedings. Its origins are found in judicial review, where it was developed by the courts to ensure that they could properly scrutinise the legality of executive action. In the seminal case of R v Lancashire County Council, ex parte Huddleston (1986), the Court of Appeal stressed that in judicial review proceedings, the parties were not adversaries in the traditional sense. Instead, the court and the public authority were engaged in a common enterprise to ensure that public power was exercised lawfully. Sir John Donaldson MR stated that in such cases, public bodies should "make full and fair disclosure" (p. 243) of the relevant facts and reasoning behind their decisions.
The purpose of this duty is threefold. First, it ensures procedural fairness by providing an applicant and the court with the necessary information to understand and challenge a decision. Without it, the "information asymmetry" between the citizen and the state would make effective scrutiny almost impossible (Elliott and Varuhas, 2017). Second, it upholds the rule of law by compelling public authorities to expose their decisions to legal challenge, thereby discouraging unlawful or arbitrary action. Third, it promotes public trust by demonstrating that government bodies are willing to be held to account for their conduct.
The duty has seen particular development in the context of inquests into deaths where the state is implicated. The procedural obligation under Article 2 of the European Convention on Human Rights (ECHR), the right to life, requires an effective and independent investigation into such deaths. The Supreme Court has confirmed that this includes a duty of candour on the part of state bodies participating in an inquest, to ensure the coroner and the family can understand "how the deceased died" (R (on the application of C) v Secretary of State for Justice, 2008). It is in this context, where bereaved families seek the truth, that the clash with national security secrecy becomes most acute.
The National Security Justification for Secrecy
The argument for exempting national security bodies from the full force of the duty of candour rests on the unique nature of their work. Unlike other public bodies, their core function often depends on the ability to operate in secret. Disclosing certain types of information could have severe and far-reaching consequences.
First and foremost is the argument from operational necessity. National security bodies rely on sensitive techniques, sources, and methods (TSMs) to gather intelligence on threats such as terrorism and hostile state activity. Public disclosure of these TSMs could render them useless, alerting adversaries and allowing them to develop countermeasures. This would undermine the very ability of the agencies to protect the public. The longstanding government policy of "neither confirm nor deny" (NCND) in relation to intelligence matters is a manifestation of this principle, designed to avoid inadvertently revealing what is known or not known to the agencies (Fenwick, 2017).
Second, there is the critical issue of protecting personnel. The safety of intelligence officers, agents, and informants depends on their identities remaining confidential. Disclosure could directly expose them and their families to grave danger. The fear of such exposure would also have a chilling effect, making it significantly harder to recruit human sources in the future, thereby damaging a vital intelligence-gathering capability.
Third, national security often involves cooperation with international partners. Intelligence is frequently shared between allied nations on the strict understanding that it will be protected. A failure to safeguard this information could lead to a loss of trust, a breakdown in these crucial relationships, and a denial of access to vital intelligence in the future. As such, the state argues that it has a compelling public interest in maintaining secrecy to protect not only its own operations but also its international standing and capabilities. These arguments collectively suggest that an unqualified duty of candour is incompatible with the effective functioning of a state's security apparatus.
Challenging the Case for Exemption: Accountability and the Right to Truth
Despite the force of these arguments, the case against a blanket exemption for national security bodies is equally, if not more, compelling from a constitutional perspective. An absolute exemption would create a serious accountability deficit, placing these powerful state bodies beyond a fundamental aspect of the rule of law.
The primary counterargument is that no part of the state should be immune from accountability. The duty of candour is a mechanism for ensuring that public bodies, including those with coercive powers, operate within the law. To exempt them would be to accept that a part of the state can operate in a legal 'black hole', free from effective external scrutiny. This is problematic in a democracy committed to the rule of law. As Lord Bingham famously argued, the rule of law requires that all are "bound by and entitled to the benefit of the law" (Bingham, 2010, p. 8), and this must include the security services.
This principle finds its most powerful expression in the context of bereaved families seeking answers. In cases such as the 7/7 London bombings or the Manchester Arena attack, families of victims have a profound interest in understanding not just what happened, but whether any failings by the security services contributed to the loss of life. Denying them access to relevant information on the grounds of a blanket national security exemption would frustrate their search for truth and prevent lessons from being learned to prevent future tragedies. This "right to truth" is closely linked to the state's procedural duties under Article 2 of the ECHR, which demands an investigation capable of identifying and, where appropriate, holding responsible those whose actions or omissions caused the death (Jordan v United Kingdom, 2001). A process where the state can unilaterally withhold crucial information cannot be considered an effective investigation.
Furthermore, excessive secrecy can be counter-productive. While transparency can carry risks, a complete lack of it can erode public confidence in the institutions designed to protect them. In the absence of official information, suspicion, mistrust, and conspiracy theories can flourish, damaging the legitimacy of the security services and hindering public cooperation. A measure of supervised transparency, by contrast, can bolster public confidence by demonstrating that the agencies are subject to robust oversight.
A Middle Way? The Role of Judicial Oversight and Special Procedures
The English legal system has not opted for a blanket exemption but has instead developed specific procedures to manage the conflict between open justice and national security. This approach implicitly acknowledges that candour is the default position, and any departure from it must be specifically justified and controlled. The two principal mechanisms are Public Interest Immunity (PII) and Closed Material Procedures (CMPs).
PII is a common law doctrine that allows evidence to be withheld from legal proceedings where its disclosure would cause real harm to the public interest. Crucially, a government minister’s assertion that disclosure would be harmful is not final. The ultimate decision rests with a judge, who must perform a balancing act, weighing the public interest in the administration of justice (which favours disclosure) against the public interest in protecting the information (Conway v Rimmer, 1968). This ensures judicial oversight and prevents the executive from being the judge in its own cause.
However, PII is an "all or nothing" solution: the material is either disclosed or excluded entirely. This was seen as inadequate in cases where excluding sensitive evidence would prevent a case from being justly tried at all. In response, Parliament passed the Justice and Security Act 2013, which allows for the use of CMPs in certain civil proceedings involving national security. In a CMP, an individual and their normal lawyers are excluded from hearings where sensitive evidence is considered. Their interests are represented by a security-cleared "Special Advocate". The judge sees all the material and can therefore reach a decision based on the full picture.
These mechanisms are controversial. Critics argue that CMPs in particular fundamentally undermine the principles of natural justice, as a party cannot fully answer a case based on evidence they have not seen (King, 2014). Families involved in inquests have often expressed deep dissatisfaction with a process that leaves them feeling excluded and unable to participate fully. The Supreme Court itself resisted the judicial development of such procedures in Al-Rawi v The Security Service (2011), holding that it was a step that only Parliament could take. Nevertheless, these procedures show that the law's response is not a blanket exemption from candour, but rather a structured, albeit contentious, attempt to reconcile the competing interests through judicial supervision.
Conclusion
The question of whether national security bodies should ever be exempt from the duty of candour touches upon the core principles of democratic governance. The arguments for secrecy, rooted in operational effectiveness and the safety of personnel, are serious and substantial. However, they do not justify a complete or automatic exemption from the duty of candour. To grant one would be to abandon the constitutional imperative of accountability and deny the right to an effective remedy and the right to truth, particularly for those bereaved by state failures.
The current legal framework in England and Wales, which relies on judicially supervised mechanisms like PII and statutory schemes like CMPs, represents a complex and imperfect compromise. These procedures effectively create a qualified and partial exemption from the public disclosure aspect of candour, but they do not exempt the agencies from being candid with the court itself. This preserves a critical line of accountability. While the fairness of these procedures, especially CMPs, is a subject of legitimate and ongoing debate, they are preferable to a blanket immunity that would leave the actions of security services entirely in the shadows. The duty of candour remains the baseline standard. Any deviation from it in the name of national security must be specifically justified on the facts of the case, narrowly tailored to the risk, and, most importantly, subject to the final determination of an independent judge.
References
Al-Rawi v The Security Service [2011] UKSC 34.
Bingham, T. (2010) The Rule of Law. Allen Lane.
Conway v Rimmer [1968] AC 910.
Elliott, M. and Varuhas, J. (2017) Administrative Law: Text and Materials. 5th edn. Oxford University Press.
Fenwick, H. (2017) ‘National security and the duty of candour in the light of the Justice and Security Act 2013’, in M. Elliott and D. Feldman (eds.) The Cambridge Companion to Public Law. Cambridge University Press.
Jordan v United Kingdom (2001) 37 EHRR 2.
Justice and Security Act 2013.
King, T. (2014) ‘Closed Material Procedures: The Liversidge Legacy?’. Cambridge Law Journal, 73(1), pp. 23-27.
R (on the application of C) v Secretary of State for Justice [2008] EWCA Civ 882.
R v Lancashire County Council, ex parte Huddleston [1986] 2 All ER 941.
