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Mandatory Detention for all Irregular Arrivals, and Funding a Detention Centre in France? The Latest from the UK

An image promoting the “Illegal Migration Bill,” shared by Prime Minister Rishi Sunak on Twitter (source:

Over the past week, the UK has proposed a number of controversial and extraordinary measures aimed at stopping irregular migration, including proposing new legislation that imposes mandatory detention for anyone crossing the Channel by boat as well as a joint initiative with France that includes helping pay for a new detention centre there.

On 7 March, the UK government tabled the Illegal Migration Bill, which would require authorities to immediately detain for 28 days anyone who arrives in the UK via an irregular route, including across the Channel. This would apply to all arrivals, including families with children and unaccompanied children. After 28 days, detention orders could be extended so long as there is a “reasonable prospect of removal,” and detainees would not be able to challenge these orders. The bill has promoted outrage and disbelief because it appears to be wholly unworkable and is also in direct violation of the UK’s international obligations. UNHCR says the law would be a  “clear breach” of the 1951 Refugee Convention. 

On 10 March, UK Prime Minister Rishi Sunak and French President Emmanual Macron announced a joint, multiyear financial package also intended to stop irregular migration across the Channel. The deal will see hundreds more French personnel patrolling French beaches and the deployment of additional drones and surveillance technology to intercept and stop small boats. Sunak also agreed to the UK co-financing a new detention centre in France, which may represent the first time that a major industrialised country has agreed to finance immigration detention centres in another industrialised country. 

The Illegal Migration Bill 

The Illegal Migration Bill would dramatically expand UK detention and deportation powers. With the exception of unaccompanied children, all people who arrive irregularly will automatically have their asylum claims deemed inadmissible–meaning that authorities will never even consider their applications for protection. Instead, the legislation proposes deporting every arrival to their own country or a “safe third country” like Rwanda, and banning them from ever applying for asylum in the UK. 

Numerous observers contend the proposed law is wildly unrealistic. In 2022, 45,755 men, women, and children arrived in the UK via small boats. Already, nearly 3,000 have crossed this year. As of 2023, the country has 2,335 detention spaces (in seven immigration removal centres, and three short-term holding facilities). To detain all arrivals would require a massive expansion of detention spaces, prompting some observers to speculate that authorities would utilise more ad-hoc facilities like Manston Processing Centre, a former military base used as a short-term holding facility which was denounced in 2022 for severe overcrowding and unsafe, unsanitary conditions. 

The government, however, has failed to clarify where it would detain the thousands of arrivals. Although it said that new detention centres would be opened–including on military bases–when pressed in a TV interview, Home Secretary Suella Braverman could not provide any specific details. Instead, she emphasised that there are “logistical challenges.” 

The UK’s ability to deport tens of thousands of arrivals also remains questionable. 

Refugees and asylum seekers cannot be returned to countries where their lives would be in danger as this would be a breach of the fundamental principle of non-refoulement. They can’t be returned to countries they may have passed through in Europe, as the UK has no return agreements with EU states post-Brexit. And while the government has mentioned returning people to “safe third countries”, such as the Rwanda, these arrangements currently do not exist. The Rwanda scheme is still being challenged in court, and even if it is approved, it is unlikely to start until late 2023, or early 2024. 

Analysts and commentators have painted a bleak picture of a huge, growing backlog of people indefinitely trapped in a sprawling detention estate which fails to meet basic needs. As Colin Yeo writes, “If we imagine how the asylum system might look at the start of 2024, it is hard to see how it will look good for the government. Even if Rwanda or other safe country flights begin some time around then, there will already be a huge backlog of tens of thousands of people to remove, many of whom will have disappeared into the community.” 

Analysts have also argued that the bill is incompatible with the UK’s obligations under international treaties such as the 1948 Universal Declaration of Human Rights, which enshrines the rights of all people to seek and enjoy asylum from persecution; the 1951 Refugee Convention which states that refugees should not be punished for the means by which they travel to a country of asylum, or for entering illegally; and the European Convention on Human Rights–all of which were international instruments that the UK helped to draft. Braverman herself told MPs that “there is more than a 50 percent chance” that the new provisions may not be compatible with international law. 


What We’re Reading:

Colin Yeo: “What is the Illegal Migration Bill?”

Border Criminologies: “Border Control as Politics” 

Steven Swinford:“Sunak’s Small Boats Plan – The Challenges”

Arbitrary detention children Europe Indefinite Detention Refugees and Asylum Seekers United Kingdom