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Immigration Detention in the UK

20 May 2020

This briefing provides an overview of immigration detention in the UK. It discusses the capacity of the UK’s detention system, the number of people detained, their characteristics, and lengths of detention. It also examines the detention of children and the financial costs of operating the system.

  1. Key Points
    • Around 24,400 people entered immigration detention in the UK in 2019, the lowest number since 2009.
    • In 2019, 73 children were detained for immigration purposes, down from around 1,100 in 2009.
    • From 2010 to 2019, citizens of ten countries contributed over half of all people entering immigration detention.
    • Around half of those entering immigration detention have claimed asylum in the UK.
    • The Home Office estimates that 112 or more members of the Windrush generation may have been unlawfully detained.
    • From 2009 to 2019, the daily population of immigration detainees ranged from around 1,600 to 3,500, and fell to a low of around 750 in March 2020 because of releases, likely due to the coronavirus pandemic.
    • Around one-third of immigration detainees are held for longer than 28 days.
    • From 2010 to 2019, there has been a significant increase in the proportion of detainees released on bail conditions.
    • In the fourth quarter of 2019, the daily cost for each detainee was about £95.
  1. Understanding the Policy

    Immigration detention refers to the Home Office practice of detaining foreign nationals for the purposes of immigration control. Policy reasons for detaining typically include one or more of the following: to effect the person’s removal; to establish their identity or the basis of their immigration or asylum claim; where there is reason to believe they will abscond if released on bail; or when release is not considered to be ‘conducive to the public good’. In some instances, the reasons for a person’s detention change while he or she is being held. Detention typically ends in either removal from the UK, or release into the community, usually on immigration bail. ... Click to read more.

    The Home Office has the administrative power to detain a person at any point in their immigration process. This includes: 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; following arrest by a police officer; or after the conclusion of a prison sentence.

    The Home Office detains people mostly in Immigration Removal Centres (IRCs); Short-Term Holding Facilities (STHFs); pre-departure accommodation facilities (PDAs); short-term holding rooms based at ports of entry; and prisons. Immigration detention is an administrative process, rather than a criminal justice procedure, meaning that the decision to detain a person is typically made by Home Office civil servants rather than the courts. On 31 December 2019, 77% (1,254) of those in immigration detention were held in IRCs, 1% (24) in STHFs, and nobody was held in pre-departure accommodation (the fourth type of facility, short-term holding rooms, are not included in these counts). It is notable that 22% (359) were held in prisons under immigration powers, up from 10% (330 out of 3,455) in the third quarter of 2017, when statistics on the number of people detained in prisons first began to be officially published. This is because while the number held in prisons has remained largely constant, the total number of people in immigration detention has fallen.

    Detention is supposed to be used as a last resort. According to Home Office policy and international law, “Detention must be used sparingly, and for the shortest period necessary” (UK Visas and Immigration, 2016, para. 55.1.3). As of 15 January 2018, Schedule 10 to the Immigration Act 2016, on Immigration Bail, introduced automatic bail hearings for detainees. Detention beyond this period must be authorised by senior officials within the Home Office. Unlike other EU countries, there is no upper time limit on how long a person can be detained in the UK. (see below)

    The UK detention system

    As of 31 December 2019, in the UK, there were seven IRCs (Brook House, Colnbrook, Dungavel, Harmondsworth, Morton Hall, Tinsley House, and Yarl’s Wood); two STHFs (Manchester Residential STHF, formerly Pennine House; and Larne House); one pre-departure accommodation facility at Gatwick Airport; several holding rooms in ports, airports, and at reporting centres across the country; and HM Prisons. There are also short-term units within some IRCs, including at Colnbrook and Yarl’s Wood. All of these facilities are in England, except for Dungavel IRC in Scotland, and Larne House STHF in Northern Ireland.

    The UK Border Force operates four STHFs in Northern France as part of the juxtaposed controls system established by the Sangatte and Touquet treaties. Two STHFs are in Coquelles, inside the Eurotunnel site, and one is at the port of Calais. The private contractor Mitie Care and Custody holds the contract to manage these three STHFs. Eamus Cork Solutions manages the fourth STHF, which is in Dunkerque (Dunkirk).

    There are 14 reporting centres in the UK, which are where some detainees are first detained and where many must subsequently report as a condition of their release. In March 2020, the Home Office announced that reporting as a condition of immigration bail was temporarily suspended due to the Covid-19 coronavirus pandemic situation.

    Except for Morton Hall IRC, which is managed by HM Prison Service, the Home Office has outsourced the management of its IRCs to large private firms – Mitie, G4S, Serco, and the GEO Group. In 2011, the contract for managing the holding rooms, and two of the three STHFs, passed to Reliance (now Tascor). From 21 May 2020, Brook House and Tinsley House IRCs will no longer be operated by G4S, whose contract is passing to Serco (GOV.UK, 2020).

    Several IRCs have been closed in recent years as part of a planned reduction of the size of the UK’s detention system. IRCs Dover and Haslar closed in 2015, The Verne closed in December 2017, and returned to its previous purpose as a men’s prison, and Campsfield House IRC was closed on 14 December 2018.

    Between 2011 and 2016, the Cedars Pre-Departure Accommodation operated in West Sussex, where the charity Barnardo’s oversaw welfare services delivered to families detained for short periods before removal. A ‘discrete self-contained unit’ at Tinsley House IRC opened to accommodate families in May 2017, with G4S responsible for welfare services until Serco take over in May 2020. Families can be held for up to 72 hours, with a ministerial declaration required to extend a family’s stay to no more than seven days in ‘exceptional’ cases.

    EU citizens

    Until the end of the Brexit transition period, EU citizens have free movement access to the UK and are not generally subject to British immigration control. In this briefing, the “EU” includes Switzerland and the three additional EEA countries – Iceland, Lichtenstein, and Norway – none of which are subject to immigration control. Despite the stronger protections afforded to deportees who are EU citizens under European Union legislation than are available to third-country nationals facing removal, EU nationals can be detained in the UK prior to removal, usually as a result of criminal offending or ‘misuse’ of their Maastricht Treaty rights (i.e., for being destitute or unemployed).

  1. Understanding the Evidence

    The publicly available data on immigration detention are found primarily in publications of the Home Office and Her Majesty’s Inspectorate of Prisons (HMIP). These detention statistics record people detained under Immigration Act powers, and not foreign nationals serving criminal sentences. The statistics also exclude people detained for less than 24 hours in short-term holding rooms at ports and airports, and in police cells. ... Click to read more.

    Data on those entering detention are counts of the number of occurrences rather than the number of unique individuals. One individual may enter detention multiple times in a given period – for example, if they have left detention and subsequently been re-detained – and such an individual would be counted multiple times in the data. Nevertheless, in this briefing we use the term “people entering detention” for ease of expression. Data on those entering detention through prisons is included from Q3 2017 onwards, but 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 dependants. As such, counts for Q3 2017 and after are not comparable with those for earlier periods.

    Data on those in detention relate to those in detention on the last day of the quarter.

Around 24,400 people entered immigration detention in the UK in 2019, the lowest number since 2009

From 2009 to 2019, the number of people entering detention has ranged from around 24,000 to 32,000 per year (Figure 1).

In the year ending December 2019, around 24,400 people entered detention, the lowest level since 2009 when the Home Office began publishing official detention statistics.

In any given year, the vast majority of those entering detention are men, ranging from 81% to 86%.

Figure 1

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In 2019, the Home Office detained 73 children for immigration-related purposes, down from around 1,100 in 2009

There are very few people over the age of 50 in immigration detention: in 2019, 94% were under the age of 50 and almost half were under 30 years old (47%) (Figure 2).

In the 1990s, the Home Office rarely detained families with children. Between 2005 and 2009, non-governmental organisations and other groups estimated that the number of children detained with their families stood at up to 2,000 per year (Crawley and Lester, 2005; Sankey et al., 2010).

Home Office statistics record that in 2009 1,119 children entered detention. After a policy change under the Conservative and Liberal Democrat coalition government, and the opening of Cedars pre-departure accommodation near Gatwick in 2011, the number of detained children fell substantially, standing at 73 in 2019 (Figure 2).

Figure 2

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From 2010 to 2019, citizens of ten countries contributed over half of all people entering immigration detention

Of the roughly 24,000 people who entered immigration detention in 2019, 62% were citizens of ten countries (Table 1). In part, these patterns reflect the total number of people of each nationality in the UK. The number of EU nationals entering detention has significantly increased over the past decade, from 768 in 2009, to 3,942 in 2019, or 16% of all those entering detention (Figure 3).

Table 1

Figure 3

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Around half of those entering immigration detention have claimed asylum in the UK

There are several categories of people who are detained under Immigration Act powers, with some individuals falling into more than one category. These categories include: new arrivals awaiting examination by an immigration officer to determine their right to enter the UK; new arrivals who have been refused permission to enter the UK and are awaiting removal; those who have either failed to leave the UK on expiry of their visas (visa overstayers), or who have not complied with the terms of their visas, or have attained their visas by deception; and people in the UK who are awaiting a decision on whether they are to be removed, or who are awaiting their removal, such as refused asylum seekers.

The largest category of immigration detainees is people who have sought asylum at some stage during their immigration process, including while in detention. In 2019, detainees who had sought asylum accounted for 58% (14,086) of people entering detention (Home Office, 2020a).

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The Home Office estimates that 112 or more members of the Windrush generation may have been unlawfully detained

In some cases, long-term legal residents or even British citizens who are unable to prove their status have been detained, as illustrated by the 2018 Windrush situation (see Williams, 2020). The Home Office Windrush Historical Cases Review examined the immigration records of 11,800 British residents of Caribbean Commonwealth nationality who were born before 1973 and who had been held in immigration detention or removed from the UK since 2002. The review found that 112 such members of the Windrush generation had been detained, of whom 31 were removed (Home Office, 2019b; see also Williams, 2020). The government has not been able to confirm whether all of these individuals were in fact unlawfully detained, because it has not been able to trace nine of them.

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From 2009 to 2019, the daily population of immigration detainees ranged from around 1,600 to 3,500, and has fallen to a record low, likely due to the Covid-19 pandemic

The UK has one of the largest immigration detention systems in Europe (Global Detention Project, 2019). After the closure of IRCs The Verne, Dover, Cedars, and Campsfield House, the capacity of the immigration detention system stood at around 3,200 (Shaw, 2018).

From 2009 to 2019, the Home Office has detained between 1,600 and 3,500 people at any given time (Figure 4).

At the end of December 2019, there were 1,637 people detained under Immigration Act powers, including 359 people detained in prisons. This is the lowest number since comparable statistics have been available. The fall in numbers after 2015 likely resulted in part from the end of the Detained Fast Track policy, which from 2000 until July 2015 enabled the detention of asylum seekers if a quick decision on their case was likely; and from the closing of IRCs Dover and Haslar in 2015 (which provided approximately 600 places in combination), and The Verne IRC in 2017 (an additional 600 places).

Home Office analysis has suggested that further falls in the detained population in 2018 might have resulted from (1) the commencement on 15 January 2018 of Schedule 10 to the Immigration Act 2016, on Immigration Bail, which introduced automatic bail hearings for detainees four months after entering detention; and (2) changes to the immigration system following the Windrush situation (Home Office, 2019a). Post-Windrush changes included caseworker decisions being checked by colleagues, and increasing face-to-face contact time between caseworkers and detainees (Joint Select Committee on Human Rights, 2019).

The Home Office reported that as at 21 April 2020, there were 708 people detained in the UK, including 340 in prisons (Stevens, 2020). The fall of over 900 detainees from 31 December 2019 to 21 April 2020 appears to have been driven in large part by the Covid-19 pandemic.

In March 2020, the charity Detention Action took legal action against the government, challenging the lawfulness and safety of continued immigration detention during the Covid-19 pandemic and calling for release of all immigration detainees. The case was dismissed by the High Court, but nonetheless the Home Office stated that they would review the cases of all people detained. Many people have been released on immigration bail and removals from the country significantly reduced, with removals to some countries suspended entirely.

Figure 4

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Around one-third of immigration detainees are held for longer than 28 days

In the UK, there is no statutory upper time limit for the period that an individual can be held in immigration detention. Of all those leaving detention from 2010 to 2019, 66% had been detained for less than 29 days, 17% for 29 days to under 2 months, 14% for 2 months to under 6 months, 3% for 6 months to under 1 year, and just under 1% had been detained for 1 year or longer.

In Q4 2019, 78% of those leaving detention had been held for 28 days or fewer (Figure 5).

Campaign groups and health professionals have argued that the uncertainty surrounding lengths of detention is harmful to detainees and their family and friends. Various stakeholders have argued for legislating a maximum limit on individual periods of detention, including: HM Chief Inspector of Prisons (2017); the All Party Parliamentary Group on Refugees and the All Party Parliamentary Group on Migration (2015); and the House of Commons Home Affairs Committee (2019). The revised EU Returns Directive, currently before the European Parliament, sets out a formal standard of a 6-month time limit with a maximum timeframe of 18 months for administrative detention; currently, some  European countries have legislated shorter time limits (such as 60 days in Spain and 90 days in France) after which the detainee must be released.

Figure 5

From 2010 to 2019, the share of people leaving immigration detention to be removed has significantly declined, from 64% in 2010 to 37% in 2019; whilst the share of people leaving detention through release on immigration bail has increased, from 34% in 2010 to 61% in 2019 (Figure 6).

Figure 6

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In the fourth quarter of 2019, the daily cost for each detainee was about £95

The annual cost of detention for the year ending March 2019 was £89 million, down from £108 million for the previous year (Home Office, 2019, p.135). In the last quarter of 2019, the estimated average daily cost of holding someone in immigration detention was £94.56, an increase of £7 on the cost in 2018 (Home Office, 2020d).

Courts may order the Home Office to compensate people who have been unlawfully detained. In the year ending March 2019, there were 312 proven cases of wrongful detention, for which £8.2m compensation was paid, up from 212 cases totalling £5.1 million in 2017–18.

Evidence Gaps and Limitations

There are two notable deficiencies in the available data on immigration detention in the UK. First, as mentioned, it is not possible to track individual trajectories of detention, release, and re-detention through the statistics, because the Home Office presents separate numbers of occurrences. Second, the Home Office does not provide information in the public statistics about how many people are being held on which policy ground for detention, and whether they have been released from detention or removed from the UK.

With thanks to Mary Bosworth, Ali McGinley, and officials at the Home Office for comments on an earlier version of this briefing. We are also grateful to CJ McKinney of, and Bella Sankey of Detention Action, for thorough and detailed comments on the 2020 update of this briefing. Final thanks to Frances Timberlake of Refugee Rights Europe, for highlighting the issue of short-term holding facilities in Northern France.


Related Material

  1. Media Coverage
    • Independent (26 Oct 2016)

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