Detention of migrants:
law, human rights and alternatives

Miguela Xuereb / Newsbook

«Undocumented people are people. Let’s treat them as such»


Despite being a contested topic, the detention of migrants continues to be a reality and, therefore, its discussion remains as important as it was in the beginning. If you are not familiar with the topic, this is the perfect article for you! In summary, we have tried to offer an overview of the detention of migrants and to present the grounds for detention at a European and national level. Please take into consideration that this is a very wide topic (specifically in juridical terms), hence,  there would be much more to say and explain. We hope you like it.



  1. Detention of migrants: law and human rights violations

The detention of migrants is not new.  In fact, it is believe to have started in the 1990s  as a practice used to address a mass influx of migrants at the borders or to enforced returns. It encompasses the detention of migrants (including asylum seekers), that failed to comply with immigration or residency rules. It is an administrative process, not a criminal procedure. 


According to the European Migration Network Glossary, detention is a «non-punitive administrative measure ordered by an administrative or judicial authority to restrict the liberty of a person through confinement so that another procedure may be implemented». 


Bearing in mind that these measures go against one of the most fundamental human rights – the right to liberty of person-, the legal instruments implemented by the European Union set out the specific grounds based on which an individual can be deprived of liberty, as well as the key legal principles and safeguards of international protection and return procedures.


Be that as it may, according to international and regional human rights standards, detention should only occur in circumstances where alternatives have been assessed as not sufficient and for that reason, it can only be used as a last resort and for the shortest period,  upholding the principles of necessity and proportionality. 


Under the European law, states are allowed to apply for immigration detention:


  • to prevent entry to their territory, 


  • to carry out return/deportation 
  • or intra-European transfer (Dublin procedures)  
  • during asylum procedures. 

However, states have discretion to determine the detention conditions. 


Thousands of people in Europe are held in immigration detention, even though the vast majority of them have never committed a crime. According to the Platform for Undocumented Migrants (PICUM), «the majority of people in an irregular situation entered the territory of the EU legally (…). Individuals seeking protection are entitled to cross borders without valid travel papers. It is the fact of remaining in the EU when their visa expires after failing to secure long-term residency or following the rejection of their asylum application which places them in an irregular situation».


Significantly, managing migration through privation of freedom of movement has severe impacts on people, since it acts as fertile ground for violations of human rights. Being deprived of liberty for migration-related reasons in a detention center, among others, causes a feeling of uncertainty. In keeping with Sarah Turnbull, in “Stuck in the middle”: Waiting and uncertainty in immigration detention“ the author enhanced that detainees see their days filled with bureaucratic and institutional issues since the time is controlled by authorities.


What is more, the World Health Organization,  stated that «the environment in immigration detention can cause a decline in the mental health of migrants. The longer migrants are detained, the worse the effects on their mental health. These negative impacts can be long-lasting, continuing even after release».  Whilst,  PICUM  mentions that «even short periods of detention leave strong marks on people’s future, increasing their vulnerability to harm», advocating that «those in a pre-existing situation of vulnerability and children should never be detained, as the harms of detention are always disproportionate and unjustified». 


Thereupon, if detention facilities are «harmful, expensive, and ineffective as a deterrent» (Jordana Signer, 2021),  which alternatives, more humane and rights-respecting approaches, to detention should be used?  



  1. Alternatives to migrants detention: theory and practice

Using the narrow sense for asylum seekers, United Nations High Commissioner for Refugees  (UNHCR) has defined alternatives to immigration detention as «any legislation, policy or practice that allows asylum-seekers to reside in the community subject to a number of conditions or restrictions on their freedom of movement». 

The use of these alternatives has been voiced by NGOs and the European Union. The International Detention Coalition in the study “There Are Alternatives: A Handbook for Preventing Immigration Detention” refers that «these solutions besides respecting the human rights of refugees, asylum seekers, and migrants, are incredibly effective at achieving migration management objectives without the need for potential human rights violations. Besides, they are more affordable and significantly more cost-effective than custodial detention». 


Namely, Human Rights Watch reckoned that community-based case management programs «provide a holistic set of services, including access to legal aid and guidance on securing basic necessities such as housing and employment». Also, JRS underlined that ensuring such alternatives to detention should «include individual professional accompaniment for each asylum seeker and migrant involved, to reach the correct solution for their individual situation, such as the return to the home country, a protection status or regularisation».


Furthermore, the International Organization for Migration (IOM) plays a key role in the field of immigration detention focusing on the promotion of alternatives to detention «providing governments with related policy support, as well as improving migrants’ living conditions in detention centers according to international standards and best practices». 


In this regard, the most frequently available alternatives to detention in the European Union Member States are the following: the requirement to reside at a designated place, the obligation to surrender an identity or national travel document, the obligation to communicate address to authorities and release on bail (with or without surety). While, in some Member States, third-country nationals can provide a deposit or financial guarantee to ensure that they can remain on the territory of the country, return counselling, Community management programs, or case workers.


However, in practice, the “Report Detention and Alternatives to detention in international protection and return procedure” pointed out that «Member States do not necessarily use every available alternative. For example, the obligation to reside at a designated place exists in national law in 21 Member States but is used in only 17 Member States» (Portugal being one of them).   


To conclude and quote the Professor of International Human Rights Law, Frank Schürmann, «if we bring the reality of alternative measures more closely in line with legal standards then a significant improvement is overall achieved».



  1. The case for Portugal


According to the Asylum Information Database’s (AIDA) report for Portugal, the three main detention facilities at the Portuguese border are located in  Lisbon, Porto, and Faro airports, all managed by the Portuguese Immigration and Border Service (SEF) under internal regulations.  The Unidade Habitacional de Santo António (CIT – UHSA)  is the only temporary installation center per se currently functioning in Portugal.


In the case of UHSA, the law provides for a Memorandum of understanding with IOM and JRS Portugal which are responsible for providing social, psychological, and legal assistance to migrants in detention center. Furthermore, IOM shares information materials at the facility (namely on the rights of people in an administrative situation, regular migration, and risks of irregular migration), organizes information sessions, and conducts interviews on the circumstances of detention.  Medical and psychological assistance is provided by Doctors of the World.   


As far as the length of detention is concerned, 60 days is the maximum length of time that people can be detained. For example, articles 26 and 35-A(3)(a) of the Asylum Act lays down that an asylum seeker, either at the airport or land border, “who does not meet the legal requirements for entering national territory” can be detained for up to seven days for an admissibility procedure. On the one hand, if SEF takes a positive admissibility decision or if no decision has been taken within seven working days, the applicant is released.  On the other hand, if the claim is deemed inadmissible or unfounded, the asylum seeker can challenge the rejection before the administrative courts with suspensive effect and remains detained for up to 60 days during the appeal proceedings. However, after 60 days, even if no decision has yet been taken on the appeal, SEF must release the individual from detention and provide access to the territory (Article 35-B(1) Asylum Act).


Despite the safeguards enshrined in the law that detention should only be the solution «if it is not possible to effectively implement less serious alternative measures», according to the report mentioned supra, «in  practice, criminal courts rarely conducted an individual assessment on whether it is possible to effectively implement alternatives to detention».

1 European Migration Network Glossary, available in 
2 Protected under Art. 5 of the European Convention on Human Rights (ECHR),Art. 6 of the EU Charter of Fundamental Rights, 5 and Art. 9 of the International Covenant on Civil and Political Rights (ICCPR)
3 With great importance  the Reception Conditions Directive 2013/33/ EU and Return Directive 2008/115/EC
4 According to Schengen Borders Code – Regulation 2016/399 of the European Parliament and of the Council of 9 March 2016 on a Union Code on the Rules Governing the Movement of Persons across Borders 
5 According to  the Return Directive Directive 2008/115/EC of the European Parliament and of the Council of 16 December 2008 on Common Standards and Procedures in Member States for Returning Illegally Staying Third-Country Nationals.
6 Dublin Regulation- Regulation 604/2013 of the European Parliament and of the Council of 26 June 2013 Establishing the Criteria and Mechanisms for Determining the Member State Responsible for Examining an Application for International Protection Lodged in One of the Member States by a Third-Country National or a Stateless Person.
7 The Reception Conditions Directive – Directive 2013/33/EU of the European Parliament and of the Council of 26 June 2013 Laying down Standards for the Reception of Applicants for International Protection.
8 ‘Sarah Turnbull, 2016,  ‘Stuck in the middle’: Waiting and uncertainty in immigration detention. Time & Society, 61-79
11 Sandler Fellow in the Refugee and Migrant Rights Division at Human Rights Watch in 
12 UNHCR, Detention Guidelines, 2012, § 8.  
14 For more information, please read Report Detention and Alternatives to detention in international protection and return procedure, 2022,  p.17 and ss
15 Report Detention and Alternatives to detention in international protection and return procedure, 2022,  p.33
16 Asylum Information Database (AIDA), “Country Report: Portugal”, 2022, p.141
17 Asylum Information Database (AIDA), “Country Report: Portugal”, 2022, p.158
18 Act n. 27/2008 of 30 June 2008 establishing the conditions for granting asylum or subsidiary protection, transposing Directives 2004/83/EC and 2005/85/EC 
19 Article Article 35-A(4)(a) and (b) Asylum Act
20 Consisting either of reporting duties before SEF on a regular basis or residential detention with electronic surveillance (house arrest).
21 Asylum Information Database (AIDA), “Country Report: Portugal”, 2022, p.144