The UK's "Licence to Kill", Quis Custodiet Ipsos Custodes, Secret Criminal Authorisations and Accountability

By Dr Andre Alexander, Barrister, Solicitor

Introduction

The United Kingdom's Covert Human Intelligence Sources (Criminal Conduct) Act 2021 Act ("CHISA") represents one of the most constitutionally significant developments in modern British criminal and public law.

By introducing a statutory framework which permits designated public authorities to authorise criminal conduct, including assassinations, by covert human intelligence sources ("CHIS"), Parliament has placed on a statutory footing practices that had previously operated under less explicit legal authority.

The legislation has generated considerable debate among lawyers, academics and human rights organisations. Supporters argue that it provides a clearer legal basis for covert operations which are often essential to national security and the prevention of serious crime. Critics contend that Parliament failed to include express statutory limits on the types of criminal conduct capable of authorisation, thereby creating uncertainty regarding the protection of fundamental rights.

This article considers the principal constitutional and human rights issues raised by the Act and explores the potential avenues of legal challenge available where criminal conduct authorisations ("CCAs") are alleged to exceed lawful limits.

The Statutory Framework

CHISA amended the Regulation of Investigatory Powers Act 2000 ("RIPA") by inserting section 29B, which creates the statutory regime governing Criminal Conduct Authorisations ("CCA").

A CCA permits criminal conduct by or in connection with a covert human intelligence source where an appropriately authorised officer is satisfied that the statutory conditions are met. Under its section 29B, an authorisation may only be granted where the decision-maker believes that the authorisation is:

. necessary;

. proportionate; and

. supported by arrangements required under regulations made by the Secretary of State.

Necessity may be founded upon one or more statutory objectives, namely:

. national security;

. preventing or detecting crime or preventing disorder; or

. protecting the economic well-being of the United Kingdom.

The legislation therefore creates a statutory mechanism by which conduct that would otherwise constitute criminal offences may, if lawfully authorised, become lawful for all purposes.

Designated Public Authorities

Schedule 1 to RIPA identifies the public authorities capable of granting Criminal Conduct Authorisations. These include, amongst others:

. the Ministry of Justice

. the National Crime Agency

. police forces;

. the Security Service;

. the Secret Intelligence Service;

. GCHQ;

. HM Revenue & Customs;

. the Serious Fraud Office;

. the Financial Conduct Authority;

. the Environment Agency;

. the Food Standards Agency;

. the Gambling Commission;

. certain Government departments.

The inclusion of executive departments such as the Ministry of Justice has prompted constitutional discussion concerning the breadth of executive authority under the legislation. It should, however, be noted that the Ministry of Justice forms part of the executive branch of government and should not be confused with the independent judiciary.

The Absence of Express Statutory Limits

Perhaps the most controversial feature of CHISA is not what it expressly authorises but what it does not expressly prohibit. That is because, unlike certain comparable legislation in other jurisdictions, CHISA contains no statutory schedule identifying categories of criminal conduct that may never be authorised.

As such, this legislative omission has attracted criticism because it leaves the permissible scope of authorised conduct to be determined principally by:

. the Human Rights Act 1998;

. the European Convention on Human Rights;

. public law principles;

. oversight by the Investigatory Powers Commissioner; and

. subsequent judicial interpretation.

However, government Ministers made clear during Parliamentary debates that conduct incompatible with the Human Rights Act or the ECHR could never lawfully be authorised. However, those assurances do not appear expressly within the statutory wording itself and whether Parliament should have enacted explicit statutory prohibitions remains an important constitutional question.

Human Rights Considerations

Any Criminal Conduct Authorisation granted by a public authority remains subject to the Human Rights Act 1998. Section 6 of that Act makes it unlawful for public authorities to act incompatibly with Convention rights unless primary legislation requires otherwise. Consequently, authorisations that interfere disproportionately with Convention rights remain susceptible to legal challenge.

The principal Convention provisions potentially engaged include:

Article 2 - Right to Life. Article 2 protects the right to life and permits lethal force only in narrowly defined circumstances where absolutely necessary. In particular, the decision of the European Court of Human Rights in McCann and Others v United Kingdom demonstrates that even operations involving national security remain subject to rigorous judicial scrutiny. Therefore, although CHISA creates a statutory authorisation regime, any use of lethal force would still require compliance with Article 2.

Article 3 - Torture and Inhuman or Degrading Treatment. Article 3 is absolute. Neither torture nor inhuman or degrading treatment permits derogation. Accordingly, any purported authorisation incompatible with Article 3 would almost certainly face significant legal challenge.

Article 5 - Liberty. Operations involving detention or restraint may engage Article 5.

Article 6 - Fair Trial. The use of covert operatives and evidence obtained through authorised criminal conduct may also raise questions concerning fairness of criminal proceedings.

Article 8 - Private Life. Many covert operations necessarily interfere with privacy rights. Such interference must remain proportionate.

Derogation under Article 15 - The Convention permits limited derogation during war or public emergency threatening the life of the nation. However, Article 15 itself contains significant limitations as certain rights remain non-derogable, including:

. protection against torture;

. slavery;

. retrospective criminal punishment; and

. the abolition of the death penalty under Protocols 6 and 13.

Any derogation must also be strictly necessary and consistent with the State's wider obligations under international law.

Oversight and Accountability

It would be incorrect to suggest that Criminal Conduct Authorisations exist without oversight. That is because the statutory framework provides for review by the Investigatory Powers Commissioner, who may inspect authorisations and make recommendations.

Furthermore, judicial review remains available in appropriate cases. Also, the Investigatory Powers Tribunal may also provide an avenue of challenge in matters concerning covert investigatory powers.

That said, the practical difficulty for potential claimants is not necessarily the absence of legal remedies, but rather the secrecy surrounding covert operations, issues of disclosure, standing, and national security.

Practical Limits of Oversight

Although CHISA establishes several mechanisms of oversight including review by the Investigatory Powers Commissioner, the availability of judicial review in appropriate cases, and proceedings before the Investigatory Powers Tribunal, a practical question remains as to whether those safeguards are capable of providing effective accountability in every case.

Unlike most areas of public law, the conduct authorised under CHISA is, by its very nature, intended to remain covert. Accordingly, a person adversely affected by an authorised criminal act may never become aware that the conduct was authorised, or indeed that state involvement existed at all.

Consequently, many of the ordinary safeguards inherent in the common law may never be engaged. For example, jJudicial review ordinarily requires a claimant to know that a public decision has been made; civil proceedings generally require knowledge of both the facts giving rise to the claim and the identity of the proposed defendant and criminal proceedings likewise depend upon the alleged conduct becoming known to investigators and prosecutors.

Therefore, where the very existence of a Criminal Conduct Authorisation remains secret, these conventional mechanisms of accountability may never be activated.

In practice, oversight therefore depends heavily upon internal compliance by the authorising public authority and retrospective review by independent oversight bodies rather than adversarial testing before the courts.

The Rule of Law and Constitutional Observations

This gives rise to an important constitutional observation. The rule of law has traditionally developed through open judicial scrutiny, public reasoning and the testing of executive decisions before independent courts. A statutory regime whose legality is rarely subjected to adversarial judicial examination inevitably limits the opportunities for the common law to define the boundaries of executive power.

This is not to suggest that CHISA operates outside the law or beyond judicial supervision. Rather, it illustrates the practical reality that legal accountability for covert state activity necessarily differs from accountability in ordinary civil or criminal litigation. Whether those alternative safeguards provide an equivalent level of constitutional protection is likely to remain one of the central questions arising from the Act.

Practical Limitations for Redress

The true constitutional significance of CHISA may lie not in the breadth of the powers it confers, but in the practical difficulty of ever obtaining judicial scrutiny of their exercise. A legal power whose use rarely comes before the courts is one whose boundaries are defined primarily by the Executive itself, subject only to limited and necessarily retrospective independent oversight.

Accordingly, the constitutional difficulty presented by CHISA is not simply that criminal conduct may be authorised by the State. Rather, it is that the lawfulness of such authorisations may never be tested in ordinary adversarial proceedings because successful covert operations are intended to remain permanently secret.

By way of example, suppose a covert source commits a serious assault, kidnapping, or homicide during an undercover operation, and no prosecution is ever brought because the conduct was authorised and remains secret. If neither the victim nor their family ever learns that a CCA existed, what practical opportunity is there for judicial scrutiny of the authorisation?

Consequently, the constitutional safeguards traditionally provided by open justice, public scrutiny and judicial precedent may never arise. The legality of executive action therefore depends to an unusual degree upon internal decision-making and confidential oversight rather than upon the ordinary processes of public adjudication.

CHISA illustrates the continuing constitutional tension between effective law enforcement and the protection of fundamental rights. Whilst the legislation undoubtedly provides greater statutory certainty than previously existed regarding covert criminal conduct, Parliament's decision not to include express statutory limits upon the categories of criminal conduct capable of authorisation has left important constitutional questions to be resolved by the courts.

Civil Liability

Where authorised conduct exceeds statutory authority or breaches Convention rights, several potential civil remedies may arise depending upon the facts. These may include:

. claims under the Human Rights Act 1998;

. judicial review;

. declarations of incompatibility;

. claims before the Investigatory Powers Tribunal;

. misfeasance in public office;

. false imprisonment;

. assault or battery;

. malicious prosecution; and

. other public law or private law remedies where recognised.

Each case will necessarily turn upon its own facts and upon the availability of evidence.

The Parliamentary Debate

The passage of CHISA through Parliament generated significant constitutional debate, with concerns expressed by Members of both Houses, the Joint Committee on Human Rights, legal academics and civil liberties organisations.

Supporters of the legislation argued that covert human intelligence sources have long undertaken criminal conduct as an unavoidable aspect of infiltrating organised crime and terrorist organisations. In their view, CHISA did not create new operational powers but instead placed existing practices upon a clearer statutory footing, thereby increasing legal certainty and accountability.

Critics, however, argued that Parliament had missed an important constitutional opportunity by declining to include an express statutory list of offences incapable of authorisation and amendments seeking to prohibit authorisation of offences such as murder, torture and serious sexual offences were proposed during the Bill's passage but were ultimately not adopted.

However, the government has maintained throughout the Parliamentary debates that public authorities remain bound by the Human Rights Act 1998 and that conduct incompatible with the European Convention on Human Rights ("ECHR") could never lawfully be authorised.

But, critics responded that these important safeguards should have appeared expressly within the legislation itself rather than being left to implication through external legal principles. As such, the resulting legislation reflects a deliberate Parliamentary choice to rely principally upon the Human Rights Act, judicial oversight and the rule of law to define the limits of authorised criminal conduct rather than prescribing those limits expressly within CHISA itself.

Whether that constitutional balance has been correctly struck remains likely to be a continuing subject of judicial and academic consideration.

Conclusion

CHISA is one of the most constitutionally significant statutes enacted in recent years. Whether it ultimately proves to be a carefully controlled investigatory tool or a source of continuing constitutional controversy will depend less upon the language of the Act itself than upon how authorising officers, oversight bodies and the courts interpret and apply it.

The legislation presents important opportunities for criminal defence lawyers, public lawyers and human rights practitioners to examine the proper constitutional limits of executive power while ensuring that the rule of law remains paramount, even in the context of covert operations.

Disclaimer

This article is intended solely as a general discussion of legal issues and does not constitute legal advice. The law in this area continues to develop, and readers should obtain professional advice concerning their own circumstances before taking or refraining from any action.

This article is also published on LInkedIn and is and update to a previously published version.

July 2026