National Security Act 2023

The summer blockbuster film ‘Oppenheimer’ transported cinema-goers back to the middle of the twentieth century and gave an account of the US physicist Robert Oppenheimer’s role in World War II and the Cold War, based on the book “American Prometheus” by Kai Bird and Martin J. Sherwin.

Much of the film focused on the feud between Oppenheimer and Lewis Strauss, the chairman of the Atomic Energy Commission with the centrepiece of an administrative hearing to consider the removal of Oppenheimer’s national security clearance in 1954. This was juxtaposed with his leading role on the Manhattan Project with a team of scientists who developed the atomic bomb at the Los Alamos Laboratory. The film explored the geopolitical situation and domestic context of McCarthyism in the US and the conduct and allegiances of various individuals towards different political ideologies and associations.  One of the scientists later admitted to passing secrets from the project to the Soviet Union and pleaded guilty to breaches of the Official Secrets Act in force at the time.

The National Security Act 2023 received Royal Assent in the UK on 11 July 2023.  Most provisions will come into force on date(s) yet to be confirmed.

The aim of the legislation is to modernise counter-espionage laws and tackle evolving national security threats by providing new powers to the enforcement and intelligence agencies.

The Act repeals the Official Secrets Acts 1911-1939 and sets out a number of criminal offences:

  • espionage offences, namely
    • obtaining or disclosing protected information
    • obtaining or disclosing trade secrets
    • assisting a foreign intelligence service
  • entering a prohibited place for a purpose prejudicial to the UK
  • sabotage
  • obtaining material benefits from a foreign intelligence service

The Act also creates three offences of “foreign interference” aimed at harmful conduct by a foreign power, in contrast to open and transparent diplomacy.

The principal foreign interference offence has three conditions:

  • conduct which has an “interference effect”
  • conduct which is prohibited
  • the “foreign power condition”

The Act sets out what is meant by an “interference effect”, namely:

  • interfering with the exercise by a particular person with a Convention right under the Human Rights Act 1998 (this includes, for example, freedom of expression, freedom of assembly and association and freedom of thought, conscience and religion);
  • affecting the exercise by any person of their public functions;
  • interfering with whether, or how, any person makes use of services provided in the exercise of public functions;
  • interfering with whether, or how, any person participates in relevant political processes or makes political decisions;
  • interfering with whether, or how, any person participates in legal processes under the laws of the UK; or
  • prejudicing the safety or interests of the UK

Conduct is prohibited under the Act if it constitutes an offence, or it involves coercion of any kind, or involves making a “misrepresentation” (this is aimed at what we might call “disinformation”).

A “misrepresentation” is defined as a representation that a) a reasonable person would consider to be false or misleading in a way material to the interference effect, and b) the person making the representation knows or intends to be false or misleading in a way material to the interference effect. A misrepresentation may be made by a statement or by any other kind of conduct. The Act specifically mentions that a misrepresentation may include a misrepresentation as to a person’s purpose or identity or presenting information in a way which amounts to a misrepresentation, even if some or all of the information is true.

The “foreign power condition” is met if a person’s conduct or course of conduct a) is carried out for or on behalf of a foreign power, and b) the person knows or ought reasonably to know that to be the case.

The Act provides that a foreign interference offence can be committed both by persons who intend the prohibited conduct to have an interference effect, and also by someone who is reckless as to whether the prohibited conduct will have such effect.  The other conditions must also be met.  An offence may also be committed where there is a course of conduct involving two or more persons, where a person other than the defendant has engaged in the prohibited conduct.

In addition to these offences, a new Foreign Influence Registration Scheme is being introduced. To help ensure openness and transparency, this will require the registration of arrangements to carry out political influence activities in the UK at the direction of a foreign power.

This new legislation – along with the National Security and Investment Act 2021 and the Higher Education (Freedom of Speech) Act 2023 – highlights the complex interplay of our laws designed to uphold key pillars of our democracy in these challenging geopolitical times.


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