Reviewing politics
and culture since 1913

  1. Politics
  2. UK Politics
6 March 2026

Is the National Security Act too vague?

Espionage law on trial

By David Allen Green

Not so long ago the United Kingdom had a plethora of gravely named statutes protecting sensitive government information: the four venerable Official Secrets Acts of 1911, 1920, 1939 and 1989. 

We had the theatre of people “signing the Official Secrets Act” even though the statutes bound you whether you signed or not, though sometimes you needed to be notified that it applied. The point was that the act of signing would concentrate your mind wonderfully.

And then in 2023 we had an entirely new legal regime. The Official Secrets Acts were all repealed, although the ceremony of signing them may well continue. Urban myths die hard.

A new statute, the National Security Act 2023, was enacted. The law was recast. The nomenclature of official secrets gave way to that of national security. These were to be laws for a modern age.

Subscribe to the New Statesman today and save 75%

One major change was the reformulation of the spying offences. Gone was the quaint 1911 wording of it being an offence of “mak[ing] any sketch, plan, model, or note which is calculated to be or might be or is intended to be directly or indirectly useful to an enemy”.

The new law was less sketchy. In essence, it would be a “section one offence” if a person obtained or disclosed protected information when that is prejudicial to the safety or interests of the United Kingdom and for or on behalf a foreign power.

There was also a new “section three offence”: when a person knows (or should know) that their conduct materially assisted a foreign intelligence service in carrying out UK-related activities. You will see that the new law does not need there to be an enemy. It is enough that either someone’s conduct is prejudicial to the United Kingdom and for or on behalf of a foreign power, or that it materially assisted a foreign intelligence service. These are far lower hurdles for the prosecution to jump.

Select and enter your email address Your weekly guide to the best writing on ideas, politics, books and culture every Saturday. The best way to sign up for The Saturday Read is via saturdayread.substack.com The New Statesman's quick and essential guide to the news and politics of the day. The best way to sign up for Morning Call is via morningcall.substack.com
Visit our privacy Policy for more information about our services, how Progressive Media Investments may use, process and share your personal data, including information on your rights in respect of your personal data and how you can unsubscribe from future marketing communications.
THANK YOU

The question would now be how this new, modernised regime would work in practice. Recently two researchers were arrested and charged under the old official secrets legislation for spying for China, but their trials collapsed, with the Crown Prosecution Service blaming the government. The issue there was (supposedly) showing that China was an “enemy” for the purposes of the old law.

This week there were new arrests, though interestingly the arrests were reportedly under the section three offence, and not the section one offence. This means the basis of the arrests was not that the arrestees were suspected of obtaining or disclosing protected information prejudicial to the safety or interests of the United Kingdom.

Instead the three arrests this week were on the basis of a suspicion that the arrestees were materially assisting the Chinese intelligence service in carrying out UK-related activities, and that they would know, or should have known, this was what they were doing.

The section three offence is framed in broad, fairly elastic terms. It does not require it to be shown that the conduct of the arrestees is prejudicial to the United Kingdom, merely that it would assist (in this case) the Chinese intelligence service, and that the arrestees knew or ought to have known this was the case. There does not even need to have been any communication with the intelligence service.

The arrestees have now been released on bail and must be presumed innocent. It may well be that no charges are brought. But if charges are brought under section three of the new legislation – in this or any other case – the parameters of the offence may be anxiously scrutinised by the courts.

On the one hand, the courts will often defer to the executive on questions of national security, as they do in terrorism cases. On the other, courts can be alert to the need not to construe serious offences too broadly. Allegations of espionage are a grave matter – and arrests and charges should not be brought lightly.

Crown Prosecution Service has recent and painful experience of a botched prosecution involving allegations of spying for the Chinese government. Prosecutors will not want another such fiasco, especially under this new, broad and largely untested legislation.

If there is a trial in this or any other case, it will not only be the defendants who are on trial, but the law of espionage itself.

[Further reading: What the war in Iran means for China and Russia]

Content from our partners
Lives stuck in limbo
Rare Diseases: Closing the translation gap
Clinical leadership can drive better rare disease care

Topics in this article : , ,
Subscribe
Notify of
0 Comments
Most Voted
Newest Oldest
Inline Feedbacks
View all comments