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Immigration Detention in the UK

03 Jul 2018

This briefing provides an overview of immigration detention in the UK. It discusses the size of the UK’s detention facilities, the number of detainees, the average duration of detention, and the detention of children.

  1. Key Points
    • The UK immigration detention estate is one of the largest in Europe. From 2009 until the end of 2017, between 2,500 and 3,500 migrants have been in detention at any given time
    • In 2017 27,300 people entered immigration detention compared to approximately 28,900 in 2016
    • Just over one fifth of immigration detainees are held for at least two months
    • The single most common category of immigration detainees is people who have sought asylum in the UK at some point
    • Over 1,000 children were detained for the purpose of immigration control in 2009, and this number was reduced to just under 130 in 2011. It rose to 242 in 2012. It was 42 in 2017
    • In late 2017 the estimated average cost of detention was £86 per day
  1. Understanding the Evidence

    Immigration detention refers to the Home Office practice of detaining asylum seekers and others to pursue immigration-related purposes. It is an administrative process rather than a criminal procedure.

    The reasons to hold someone in immigration detention include one or more of the following: to effect a person’s removal; to establish their identity or basis of immigration/asylum claim; where there is reason to believe that the person will fail to comply with any conditions attached to the grant of temporary admission or release, i.e. a risk of absconding; or where there is a risk of harm through trafficking or to the public. There are also occasions when the reasons for a person’s detention change while he or she is already being held.

    The UK Government has discretionary power to detain at any point of someone’s immigration process: upon arrival in the UK; upon presentation to an immigration office within the country; during a check-in with immigration officials; once a decision to remove has been issued; and after a prison sentence or following arrest by a police officer.

    The publicly available data on immigration detention chiefly originate in publications released by the Home Office and Her Majesty’s Inspectorate of Prisons (HMIP). Data and information from non-governmental organisations’ reports, Hansard texts of Parliamentary debates and formal questions and scholarly articles supplement this information.

    As of December 2018, there are seven IRCs: Colnbrook, Harmondsworth, Tinsley House, Brook House, Yarl’s Wood, Morton Hall, and Dungavel. There are also two separate Residential Short-Term Holding Facilities (STHFs): Manchester Residential STHF (formerly called Pennine House), and Larne House. There are also short-term units within some IRCs, including at Colnbrook and Yarl’s Wood. In addition, there are 19 Holding rooms at ports and 11 at reporting centres. The vast majority of facilities are in England, with one IRC in Scotland (Dungavel) and one Residential Short-Term Holding Facility in Northern Ireland (Larne House). Except for IRC Morton Hall that is managed by the Prison Service, the Home Office has outsourced the management of its IRCs to private firms – Mitie, GEO, G4S and Serco. The contract for managing the Holding rooms, and two of the three STHFs passed to Reliance (now Tascor) in 2011. Several IRCs have been closed down in recent years, as part of a planned reduction of the size of the detention estate. IRCs Dover and Haslar closed in 2015, the Verne closed in December 2017 (to be returned to its previous purpose as a men’s prison) and Campfield House IRC was shut on 14 December 2018.

    Between 2011 and 2016, the Cedars Family Pre-Departure Accommodation operated in West Sussex, where Barnardos oversaw welfare services delivered to families detained for short periods before removal. A ’discrete self-contained unit’ at IRC Tinsley House opened to accommodate families in May 2017, with G4S now fully responsible for welfare services. Families can be held for up to 72 hours, with a ministerial declaration required to extend a family’s stay, up to a week in ‘exceptional’ cases. Despite an announcement in 2016 of its closure, IRC Dungavel House in Scotland remains operative and is still open for families.

    European Economic Area (EEA) nationals have free movement access to the UK and are not subject to British immigration rules (although this is likely to change after the UK leaves the European Union). Despite the stronger protections afforded to EEA deportees under European Union legislation than those available to third-country nationals facing removal, EEA nationals can be detained in the UK, usually prior to deportation for criminal offending. The Immigration Act 2014 brought changes to the interpretation of Article 8 of the European Convention on Human Rights (the right to respect for one’s family and private life) in deportation cases, lessening the barriers to removal for foreign national offenders with families or long-term residence in the UK.

    The vulnerability of adults to harm from detention has received increased attention in recent years.  In 2018, the Home Office revised its 2016 “Adults at risk in detention” Guidance. This Guidance responds to the findings of the independent detention review by Stephen Shaw published in 2016, which identified harms for vulnerable people accruing both upon detention and as detention continues. Mr Shaw’s updated review is due to be published publicly in 2018.

The UK’s immigration detention facilities are among the largest in Europe: between 2,000 and 3,500 migrants are detained at any given time

The UK has one of the largest networks of immigration detention facilities in Europe. After the re-purposing of HM Prison Morton Hall as an immigration removal centre (IRC) in 2011 and the opening of a short term holding facility at Larne House in Northern Ireland in 2011, UK detention capacity expanded to approximately 3,500 places. As shown in Figure 1, over the past years there have been between 2,000 and 3,500 migrants detained at any given time. By December 2015 the number of people detained under Immigration Act Powers decreased to approximately 2,607, most likely as a result of the suspension of the Detained Fast Track process as well as the closing of IRCs Dover and Haslar in 2015 (which accounted for approximately 600 places in combination) and the Verne in 2018 (accounting for an additional 600 spaces). The figure rose to 3,500 people detained in October 2017, before declining to 2,500 in December the same year.

Figure 1

Source: Home Office: Immigration Statistics Table dt_11_q

Adult immigration detainees may also be detained in prisons. On 31 March 2018, about 9,300 foreign nationals were held in prisons in England and Wales, comprising about 11% of the total prison population; of this group, 358 people were detained under immigration powers (data for Q1 2018).

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Approximately 27,300 migrants entered detention in the UK in 2017

The number of people entering detention has fluctuated between 27,000 and 33,000 since 2009. Approximately 27,300 migrants entered detention under Immigration Act powers in 2017, compared to 28,900 in 2016 (UK Home Office 2018a). These statistics do not include people detained in police cells and short term holding rooms at ports and airports (for less than 24 hours), and those detained under both criminal and immigration powers and their dependents. Immigration detainees are held in Immigration Removal Centres (IRCs), Residential and Non Residential Short Term Holding Facilities (STHFs), and Holding Rooms either based at or near ports of entry and reporting centres.

A large majority of people entering detention are male. In 2017, 23,272 males and 4,059 females entered detention, meaning that 85% of those entering detention in 2017 were men.

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Just over one fifth of immigration detainees are held for two months or more

There is no upper time limit for individual periods of immigration detention in the UK. In Q4 2017, about 78% of total immigration detainees leaving detention had been held for less than two months (Figure 2). It is also not uncommon for detention to span two to four months. A small but consistent minority of detainees – about 3% – are held for between 6 and 12 months, and an additional 1% held for more than a year. Campaign groups have argued that both long detention lengths and the uncertainty of lengths of detention are harmful for individuals, and various actors such as HM Chief Inspector of Prisons (2017) and the All-Party Parliamentary Group on Migration (2015) have argued for a maximum time limit on immigration detention.

Figure 2

Source: Home Office, Immigration Statistics, Table dt_06_q

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The most common category of immigration detention is people who have sought asylum in the UK at some point in their immigration adjudication processes

There are numerous categories of people who are detained under Immigration Act powers, and these categories can overlap. For example, new arrivals may be detained awaiting examination by an immigration officer to determine their right to entry; new arrivals who have been refused permission to enter the UK and are awaiting removal may also be detained; those who have either failed to leave the UK on expiry of their visas (so-called overstayers), have not complied with the terms of their visas, or have attained their visas by deception, may be detained; and undocumented people found in the UK can be detained pending a decision on whether they are to be removed or pending arrangements for their removal. As illustrated by the 2018 Windrush ‘scandal’, this has in some cases included long-term residents and or British citizens who are unable to prove their nationality.

The largest category of immigration detainees is people who have sought asylum at some stage during their immigration processes. In 2017, asylum detainees accounted for about 47% of people entering detention (UK Home Office 2018a).

The share of people detained who are EU nationals has increased over the past decade, reaching 5,300 or 19% of those entering detention in 2017 (Figure 3). With the UK’s upcoming exit from the European Union, EEA nationals are expected to come under immigration powers, potentially leading to larger numbers of detentions and removals.

Figure 3

Source: Immigration statistics table dt_04

Since April 2006, the UK Government has prioritised the removal of foreign nationals who have been convicted of crimes. As of 1 August 2008, with the introduction of the UK Borders Act 2007, all foreign nationals who have been sentenced to a period of imprisonment of 12 months or more are subject to automatic deportation from the UK unless they fall within one of the Act’s six exceptions.

Since 2009, more than 4,000 FNOs have been deported annually. (See our briefing on ‘Deportations, Removals and Voluntary Departures from the UK’.) As of Q4 2017, foreign national offenders were detained for an average of 91 days before deportation (Home Office 2018b), down from 118 days in Q4 2016.

The policy primer on ‘Immigration Detention: Policy Challenges’ provides more context, explanation, and analysis of these issues.

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Detention of children in 2017 was much lower than the 2009 levels

Throughout the 1990s, the Home Office rarely detained families with children. Between 2005 and 2009, however, non-governmental organisations and other groups estimate the number of children detained with their families to have been up to 2,000 per annum (Crawley and Lester 2005, Sankey et al. 2010). Home Office statistics suggest that more than 1,100 children entered detention in 2009. After a policy change under the Conservative and Liberal Democrats Coalition Government, and the opening of Cedars pre-departure accommodation near Gatwick in 2011, the number of detained children fell to 127 in 2011 (Figure 3). The numbers fell to 42 children detained in 2017.

Figure 4

Source: Home Office: Immigration Statistics Table dt_01

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The financial costs of immigration detention

In answer to a 2007 request made under the Freedom of Information Act, the Home Office revealed that in 2005/6 the weekly cost per detainee ranged from £511 (Lindholme IRC) to £1,344 (Colnbrook IRC). In 2013/14: the cost of detaining someone for a year was over £36,000. The total annual cost of the detention estate was £164.4 million (All-Party Parliamentary Group 2015). As of Q4 2017, the government reported the average cost per day to hold an individual in immigration detention at £86 (Home Office 2018b).

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Evidence gaps and limitations

Some gaps and limitations in the data remain. For example, it is often difficult to track individual trajectories of detention, release and re-detention through the statistics because they are presented as separate numbers of occurrences. There is also a deficit in information about the nature of discretionary decision making by Home Office officials and judicial actors on when to arrest and detain, and when to release people from detention; this information would go some way towards illuminating the meanings of the official statistics. Such evidence gaps and limitations are important in discussions about how to access immigration detainees and provide them with services such as translation and visits.

With thanks to Mary Bosworth, Ali McGinley, and officials at the Home Office for comments on an earlier version of this briefing.


Related Material

Recommended citation

Stephanie J. Silverman and Melanie E.B. Griffiths, “Immigration Detention in the UK.” Migration Observatory briefing, COMPAS, University of Oxford, UK, May 2018.

  1. Media Coverage
    • Independent (26 Oct 2016)

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