UK needs new treason law to tackle terrorists and hostile states

The UK urgently needs a new definition of treason that will recognise the nature of the threats we face today, argues a new paper from Policy Exchange, Aiding the Enemy: How and why to restore the law of treason, by Tom Tugendhat MP, Khalid Mahmood MP, Head of Policy Exchange’s Judicial Power Project Professor Richard Ekins and barrister and former army officer Patrick Hennessey.

The Treason Act 1351, which still remains law, has been overtaken by changes in modern social and political conditions; it is not a secure ground on which to mount prosecutions. A law made in the time of Edward III is no longer appropriate more than 70 years into the reign of Elizabeth II. The law as it stands fails to mark out and punish the wrong of betraying one’s country.

This week it emerged that Home Secretary Rt Hon Sajid Javid MP has taken steps to allow the group of jihadists known as ‘The Beatles’ to be sent to America to face not only trial but – in a departure from the UK’s previous position – a possible death penalty. Yet Alexanda Kotey and Shafee El-Sheikh were both British citizens when they chose to betray their compatriots by joining and fighting for Islamic State – and a workable law of treason would have allowed for them to be prosecuted accordingly.

On Friday 20th July, Khalid Ali was jailed for life after being convicted of planning a knife attack in Westminster, having previously made bombs for the Taliban. Between 2006 and 2017, 193 people were sentenced to imprisonment for terrorism offences, more than 80 of them (including notorious hate preacher Anjem Choudary) now due for release before the end of the year.  Many of them will, like Ali and Choudary, have betrayed this country; if they had been convicted of treason and imprisoned for life, the UK would be considerably safer.

The authors recommend that:

  • Parliament should enact a new offence which would revive the law of treason and recognise that betrayal – treason – is a clear moral wrong.
  • This would specify that it is an offence to aid a state or organisation that is attacking the UK or preparing to attack the UK or against which UK forces are engaged in armed conflict.
  • This should apply to the actions of anyone in the UK; it should also apply to the actions of British citizens or settled non-citizens anywhere in the world.
  • In most cases, people convicted of treason should be sentenced to life imprisonment, a sentence which reflects the gravity of the wrong of betrayal, deters others, and incapacitates the offender.
  • At a minimum, Parliament should reform our law to follow Australia and New Zealand and thus make it clear that it is unlawful to aid the enemy either in an international armed conflict or in a non-international armed conflict.

In a Foreword, former Lord Chief Justice of England and Wales Lord Judge writes:

“Most of us have not the slightest doubt that treason is and should be a very serious crime. We need to reconsider whether the current laws against terrorism and disclosure of official secrets are adequate to cover what might be or, arguably, should be treated as treason.


“In a balanced argument, carefully setting out contrary views, this paper supports a process of modernisation. Treason, it argues, is a heinous crime. It should be marked as such. If a citizen of this country chooses to fight with the Taliban in Afghanistan against British forces, his crime is more than terrorism. It is treason, and should be prosecuted accordingly.”

Co-author Conservative MP Tom Tugendhat said:

“Betrayal, or undermining your country by helping its enemies, has always been recognised as a terrible crime. It is not just an act of violence but destroys the bonds of trust that hold a community together. That’s why the preparation or use of violence by a British citizen against our own people is such a serious threat. It undermines our common defence and political order and ought to be punished severely.  Betrayal is a breach of the duty each of us owes to our fellow citizens.


“Some argue that existing laws are sufficient to address acts of betrayal. But those laws, including the terrorism legislation, are not a substitute for a workable law of treason. They rightly focus on the violence, not the betrayal.


“In an age of rising great power competition, when states like Russia are attacking the UK in ways falling short of outright armed conflict, it is vital that our law ensures that citizens assisting hostile states or seeking to undermine the UK, can be prosecuted separate from any violence they may use. This is part of the necessary powers for the defence of the realm to ensure the stability of the country. British citizens who aid groups like ISIS, groups that intend to carry out attacks against the UK, or against UK forces are deployed abroad, betray our country and should be condemned. The law must be written to ensure they can be stopped and their betrayal is recognised as a distinct crime.”

Co-author Labour MP Khalid Mahmood said

“The law of treason has become unworkable. Enacting a new, workable law of treason, and standing ready to prosecute its breach, would help to highlight, and over time to reinforce, the duty each of us has to refrain from betraying our country.  It would signal that our political community takes seriously the obligations that we owe each other.


“One can think that one’s country is mistaken or wicked, and denounce it in strong terms, without betraying one’s compatriots.


“The sentences of imprisonment imposed on British citizens who choose to aid ISIS, or similar groups, are often manifestly inadequate.  The problem is not that sentencing judges are too lenient but that the legal framework is too limited.  Punishing treason properly is important to signal clearly that our communities condemn betrayal. In line with British law as it stands, this means life imprisonment would be the most severe penalty we could use – I do not support the use of the death penalty in any circumstances.


“Sentencing traitors to life imprisonment would recognise the gravity of the wrong they have committed and would help protect the public.”

Co-author Professor Richard Ekins said:

“The foundation of peaceful social life is the trust that we have in one another as fellow citizens, trust that is undercut when one aids the enemy.  Anyone who betrays their country in this way breaches the trust of their compatriots and threatens to weaken the trust they have in one another.


“A law made in the time of Edward III is no longer appropriate 70 years into the reign of Elizabeth II. The ancient law does not adequately address these questions, which means that it cannot serve to denounce and deter British subjects from aiding attacks on UK forces, or on the UK itself, by non-state actors, which is morally indistinguishable from aiding an enemy state in international armed conflict.  In other words, the ancient law of treason fails adequately to capture and express the vital moral prohibition on betrayal or to account for changes in modern conditions.”

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