Justice Demands Action — Why the UK Must Prosecute Daesh Crimes

The atrocities committed by Daesh — also known as Islamic State — between 2014 and 2017 represent one of the gravest human rights failures of our time.

During this period, across Syria and Iraq, Daesh waged a brutal campaign of terror against ethnic and religious minorities, including Christians, Muslims, and most devastatingly, the Yazidi people. This campaign was not only brutal and widespread; it was genocidal in intent.

The suffering inflicted is unimaginable. Thousands of Yazidis were murdered. Women and girls were abducted, raped, sold, and enslaved – many remain missing to this day. Children were indoctrinated or used as child soldiers. These were not random acts of cruelty but coordinated atrocities designed to annihilate entire communities. They meet every definition of genocide and war crimes.

Despite the unprecedented scale of Daesh’s violence, the UK Government’s response has fallen shamefully short. It fails to reflect the gravity of the crimes or deliver the justice victims and survivors deserve.

There is clear evidence and legal provision for prosecuting international crimes – including genocide, war crimes, and crimes against humanity. Yet to date, not a single UK national involved in Daesh atrocities has been prosecuted under these laws. Around 32 returnees have been charged with terrorism-related offences. While those prosecutions are welcome, they are wholly inadequate given the magnitude of the crimes. The Government has formally recognised that Daesh committed genocide against the Yazidi people – but recognition without action is not justice.

There is no justification for the UK’s inaction. Other countries have acted. Germany, for example, has successfully prosecuted Daesh perpetrators for genocide and war crimes. The UK should be leading these efforts – not lagging behind.

That’s why the Joint Committee on Human Rights has published our report, Accountability for Daesh Crimes, presented to the Government on 15 May. The message is clear: the UK’s approach to investigating and prosecuting international crimes needs a complete reset.

At present, UK law enforcement overwhelmingly focuses on terrorism offences. While that focus is understandable, it is not enough. Genocide and crimes against humanity are distinct, internationally recognised offences — and they must be prosecuted as such.

The report also exposes a critical gap in UK law. Under the International Criminal Court Act 2001, the UK can only prosecute individuals for international crimes like genocide, war crimes, or crimes against humanity if they are UK nationals or residents. This limitation must be addressed. The Government should amend the law to ensure that anyone – regardless of nationality or residency – can be held accountable in UK courts for the most serious crimes known to humanity.

Beyond legislative reform, the Government must also use its powers appropriately. There is growing concern that, rather than pursuing justice, the Government has used its powers to strip individuals of British citizenship – particularly those suspected of terrorism abroad. This approach effectively removes them from UK jurisdiction and avoids holding them accountable for their crimes. Depriving someone of citizenship must never be used as a means to escape responsibility. It cannot be allowed to become a tool of evasion, nor a way to avoid our duty to uphold justice.

Equally concerning is the UK’s apparent willingness to ignore British nationals currently detained in Syrian camps who are suspected of involvement in Daesh crimes. The report calls on the Government to take every step necessary to prosecute them in UK courts. Ongoing inaction sends a dangerous message – to victims, to perpetrators, and to the world. It suggests that the UK, once a global advocate for human rights and the rule of law, is willing to look the other way when crimes occur beyond its borders. That must not be the legacy we leave behind.

My colleagues and I on the Joint Committee on Human Rights are clear: Britain must do better. We have the legal tools. We have the institutional capacity. Most importantly, we have the moral responsibility. Sitting on our hands is not an option.

The Government must act — now — to implement our recommendations and deliver long-overdue justice to the thousands of people whose lives were torn apart by Daesh’s campaign of terror.