Migration has become more central to political and policy discourse in Europe, particularly in recent years. Political parties that use migration as a rallying piece in their platforms have become more prominent, building on the narrative of increasing irregular migration. Often, such discourse draws on data in an inflammatory way, suggesting ever mounting numbers. But a new Policy Brief, which accompanies a more detailed working paper and a new public database, suggests there has been no definitive change in the number and share of irregular migrant population in the region since the estimates made in the Clandestino Project in 2008.
Data collected in the Measuring Irregular Migration (MIrreM) project for the period 2016-2023 estimated the irregular migrant population living in 12 European countries (including the UK) at between 2.6 to 3.2 million. In particular, since 2008, estimates suggest:
- No significant change for five countries: Belgium, France, Italy, the UK, the US.
- Five countries noted a decline: Finland, Greece, Ireland, the Netherlands, Poland.
- In three countries, estimates suggest greater numbers: Austria, Germany, Spain.
However, estimates such as these need to be contextualised, as they can vary widely based on the type of data available in countries (eg, census, municipal registers), the methodology used to produce these estimates, and how migrant irregularity is defined in that country. For example, do they also include EU nationals, asylum seekers, or others with provisional or tolerated statuses? Moreover, these estimates present only a snapshot of the scale of the irregular migrant population living in a particular country at a particular time, and thus do not fully capture irregular entry flows.
Led by ICMPD Senior Researcher Maegan Hendow and Senior Policy Advisor Martin Wagner, together with research partners1, the policy brief shows both what data are available and where data are (and may remain) incomplete; and what this means to make sense of irregular migration data in Europe. It highlights the need for policy-makers and policy stakeholders to be more cautious in treating the data used to describe irregular migration trends and populations, while also flagging new developments and innovative methods for estimating the irregular migrant population being tested in MIrreM and elsewhere.
Why data must be handled carefully
As the above data suggests, while attention to irregular migration at both national and EU levels has indeed increased in public and policy discourse, its scale (since 2008) has not. Given this heightened attention, the new EU Pact on Migration and Asylum promises a number of new tools and data sources that would improve our understanding of certain elements related to irregular migration. However, gaps still remain (e.g., in terms of overstayers, social and economic aspects, how people fall into or out of status over time, secondary movements, etc). The policy brief therefore argues that we need to manage expectations in terms of what new data will and will not be able to tell.
Ultimately, the Brief highlights that we are in many ways further than we were in 2008, since Clandestino. More data is now available to better understand the phenomenon of irregular migration, and technology is much more advanced as well, offering promising new estimation methods. However, given the hidden nature of irregular migration, data and estimates will inevitably be linked to uncertainty, and therefore need to be used with caution to avoid abuse.
Therefore, where policy-makers and other stakeholders use data on irregular migration, they need do so with great care. Mishandling of data undermines informed decision-making, and can potentially reinforce bias or incite unwarranted fear. Figures on irregular migration, particularly the higher ones, can be misinterpreted or even misused by political parties and media, to promote their own agendas. As such, it can also negatively impact on and endanger those targeted by such speech or policies, including migrants and minority groups. Because of this, the policy brief elaborates clear actions needed at all levels – from data collection to policy development – to mitigate these potential negative impacts.
For researchers, regular estimation efforts, exchange on (upscaling) good practices and harmonising flow indicators would already go a long way to addressing some of the limitations inherent in the data itself. For policy-makers, it is equally critical when using and presenting irregular migration data, to be precise about what exactly has been measured, as well as to understand and clearly acknowledge the inherent limitations and uncertainties.
As MIrreM shows, clearly outlining the limitations and uncertainties alongside new data presented, helps move from black-and-white thinking to more nuance – for policy-makers to develop truly evidence-based policies and programmes in responding to such a complex issue as irregular migration.
[1] Jill Ahrens and Albert Kraler (Danube University Krems); Myriam Cherti, Denis Kierans, Lucy Leon, and Carlos Vargas-Silva (University of Oxford); Arjen Leerkes and Lalaine Siruno (Maastricht University).
In a previous episode on ICMPD’s The Migration Podcast, author Maegan Hendow discussed the MIrreM project and how governments have responded to the issue of irregular migration. It also touches upon the policy shifts and their rationale, the barriers for migrants to seek pathways out of irregularity, or even why some migrants are compelled to remain in their irregular status.
About the authors
Maegan Hendow is Senior Researcher at ICMPD, where she works on topics related to irregular migration, border control, migrant smuggling, and their intersection with fundamental rights considerations. She is also involved in projects related to skills development, notably Link4Skills.
Martin Wagner is Senior Policy Advisor on Asylum at ICMPD, where he covers issues related to the Common European Asylum System, the Pact on Migration and Asylum, Temporary Protection, complementary pathways and the intersection of asylum with border management, irregularity and return.