Towards examining and addressing the danger of unaccompanied migrant minors going missing

The paper addresses the heightened risks and systemic challenges associated with unaccompanied migrant minors (UMMs) who go missing within the EU. It situates the problem within a broader historical and statistical context of missing children, noting variability and unreliability in international data due to differing legal definitions and protocols. The core objectives are to (a) outline the specific vulnerabilities and data gaps concerning missing UMMs in the EU, (b) examine shortcomings in current practices and cross-border coordination, and (c) present a novel, technology-enabled solution developed in the EU-funded ChildRescue project. The study underscores the urgency given increased risks of victimisation (including trafficking and exploitation) and the slower, less effective responses UMMs experience compared to other missing children. It motivates the need for harmonised practices and improved stakeholder communication, drawing on insights from 26 expert interviews across four EU countries and the development of an alert system to improve prevention and response.

The review highlights pervasive data limitations and heterogeneity across EU member states regarding definitions of “going missing,” timelines for action, and reporting protocols, which hinder accurate prevalence estimates and effective response. German BKA data exemplify issues: changing clearance rates without a clear definition of “cleared” cases, potential inclusion of age-outs, and lower clearance rates and longer resolution times for UMMs compared to other missing children. Underreporting is substantial; only 47.6% of surveyed organisations reported working on missing children in migration and few could report recovery timelines. Internationally, despite nearly 20,000 unaccompanied minors among asylum seekers in 2018 and estimates of over 30,000 missing migrant/refugee children between 2014–2017 in the EU, data remain inconsistent and incomplete (e.g., lack of gender/age breakdowns). Reasons for disappearances include distrust of authorities, family reunification attempts, protracted asylum processes, lack of appropriate shelters, and exploitation/trafficking pressures. EU legal frameworks mandate guardianship for trafficked minors and equal treatment in principle; however, practical implementation is inconsistent, with irregularly migrated minors often excluded from protections. Heterogeneity in national protocols (e.g., variable reporting/response timelines, ad-hoc procedures) and policy tightening in some countries exacerbate risks. Risk assessment practices can downgrade urgency for children in care, indirectly disadvantaging UMMs. Cross-border complexities, including post-Brexit uncertainties, further impede cooperation. Overall, evidence points to systemic inequities and fragmented responses that heighten the vulnerability of UMMs when they go missing.

The study used a qualitative, expert interview approach within the EU-funded ChildRescue project and a subsequent technology-development and piloting phase. Interviews: 26 open-ended, guideline-based expert interviews were conducted in two phases across four EU countries (Germany, Denmark, Greece, UK). Phase 1 (12 interviews) served as a pre-study to identify needs and issues in handling missing children cases. Phase 2 (14 interviews) focused on information requirements and processes critical to response, informing the app/platform design. Interviewees represented diverse stakeholders: specialised police units, child protective services, NGOs (including those serving UMMs and runaways), and researchers. Recruitment occurred via email/phone and through project partner organisations acting as gatekeepers. An English open-ended guideline, translated as needed, ensured comparability. Interviews were conducted by telephone, lasting 45–90 minutes, and began with a narrative case description followed by probes on decision-making and best practices. Outputs included a prioritised information schema (adapting MCE categorisation) for different missing child scenarios (e.g., for UMMs, immigration status, context of recovery site, and risk indicators). Solution development and methodology: Social theory and qualitative insights were integrated with technical innovation to create a web platform (restricted to organisational users) and a mobile app (ChildRescue). The proposed missing-children investigation cycle consists of four phases—preparation, coordination, action, and archiving—with tailored roles and access rights for data protection. Distinct features for UMMs include pre-emptive registration upon facility arrival (with explicit consent) to mitigate information scarcity if disappearance occurs; privacy-by-design (no direct authority access via the platform, consent monitoring, GDPR-compliant pseudonymisation/anonymisation, geofenced public alerts, automatic device data deletion post-case, and control over information dissemination). Functionality includes: automatic profiling/prediction to link new cases with similar past cases and identify Points of Interest (POIs); collaboration spaces for rapid team formation and messaging (observed current team formation often >1 hour); cross-facility data sharing within the same organisation (including across borders); an “intelligent” search engine for similar-sounding names to reduce duplicate or mis-registered records; geofenced mobile alerts to the public near POIs with minimal necessary child data; and secure archiving with right-to-be-forgotten enforcement. Piloting and evaluation: Three pilot organisations—The Smile of the Child (Greece), Child Focus (Belgium), and the Hellenic Red Cross—tested the solution in two piloting phases. Total participants across pilots were 74, including 21 employees/volunteers from the Hellenic Red Cross (HRC), which focused on discovery/identification and handling of UMM disappearances. Evaluated aspects included: early registration and presence-taking; facility-level lists/overviews; early absence detection; identification in emergencies; volunteer deployment/coordination; support for parallel investigations; and real-time map-based feedback. Usability was rated on a 1–5 scale (Very bad to Very good). For HRC (top-level managers; n=5), median ratings were: Organising volunteers=4 (avg abs dev 0.33), Recruiting new volunteers=4 (0), Timely response=4 (0.2), Increasing speed of recovery=3 (0), Matching similar cases=3 (0.2), Establishing relevant locations=3 (0).

• Data and clearance disparities: In Germany, clearance rates for UMMs were substantially lower and slower than for other missing children (e.g., 2019: UMMs 80.79% vs. children 97.9% and adolescents 98.61%), with 1,165 UMMs from 2016–2019 still unaccounted for. Definitions of “cleared cases” are unclear and evolving, complicating interpretation. Underreporting and duplicate/mis-registrations further distort data.
• Systemic heterogeneity and delays: EU member states use varying timelines and protocols for reporting and responding to UMM disappearances (e.g., ad-hoc timeframes, 24–48h waiting in some facilities), increasing victimisation risk and creating discriminatory practices relative to EU-born missing children.
• Elevated risks and reduced agency: UMMs face heightened risks of trafficking/exploitation and often lack guardians/advocates, leading to lower prioritisation in risk-based policing frameworks (e.g., “no apparent risk” classifications), and decision-making influenced by smugglers or peers. Lack of social networks and trusted information sources leads to reliance on informal channels with potential for misinformation and exploitation.
• Cross-border coordination gaps: Differences in national law and practice, and potential loss of EU tools for non-EU states (e.g., post-Brexit), hinder international case handling. Responsibility diffusion and fragmented CAES protections exacerbate vulnerabilities.
• Information needs for UMM cases: Beyond general data (name, age, time/place), critical items include immigration status, health (especially mental state), family/context, intended location, context of recovery site (e.g., red-light district), access to digital/dating apps, and police warrants.
• Practical solution outcomes: The ChildRescue platform/app operationalises a four-phase cycle with privacy-by-design, early registration (with consent), profiling/POIs, collaboration spaces, geofenced alerts, and secure archiving. It has been adopted by three organisations and used in over 85 real-life cases. Pilots (n=74 across partners; HRC n=5 managers) indicate perceived improvements in volunteer organisation and timeliness (median=4), with moderate perceived gains in recovery speed and case-matching (median=3). The solution reduced team formation time and improved coordination and information control (e.g., duplication checks via similar-name search).

Findings confirm that UMMs are disadvantaged by fragmented legislation, uneven protocols, and inadequate data, resulting in slower responses and elevated harm risks. The qualitative insights helped specify information priorities and process gaps (e.g., delayed reporting, risk assessment biases), which informed the design of a socio-technical intervention. The proposed ChildRescue investigation cycle addresses key barriers: it improves preparedness through early, consent-based registration; enhances coordination via collaboration spaces and cross-facility sharing within organisations; focuses searches through profiling and POIs; responsibly engages the public with privacy-preserving geofenced alerts; and tightens data stewardship through GDPR-compliant archiving and consent management. These capabilities specifically target UMM vulnerabilities (e.g., lack of guardianship, cross-border movement, data inconsistencies) by accelerating team formation, minimising duplicate records, and facilitating international organisational coordination. While preliminary, pilot feedback suggests practical utility in timeliness and volunteer management, supporting the hypothesis that better-integrated, privacy-aware processes can mitigate risks and improve outcomes. However, broader systemic issues—such as legal heterogeneity and discriminatory practices—remain and necessitate policy harmonisation and enforcement to ensure equal protection for UMMs across the EU.

The study contributes a critical assessment of EU practices regarding missing unaccompanied migrant minors and introduces a novel, privacy-conscious investigation cycle and alert platform (ChildRescue) designed to improve preparedness, coordination, targeted action, and secure archiving. Empirical evidence from 26 expert interviews and multi-country pilots indicates the solution’s feasibility and perceived effectiveness, with deployment by three organisations and application in more than 85 real-life cases. The work underscores the persistent disadvantages UMMs face due to fragmented legislation, heterogeneous protocols, and data deficiencies. The authors call for homogeneous, non-discriminatory EU-wide legislation and practices that ensure equal treatment for all missing children, and for future research that actively involves UMMs to better understand their experiences and needs before and during disappearance. Further rigorous evaluations of alert systems’ effectiveness and long-term outcomes are encouraged.

• Data limitations: International and national data on missing children—especially UMMs—are inconsistent due to differing definitions, reporting protocols, underreporting, and duplicate/mis-registrations; clearance metrics (e.g., in Germany) lack clear definitions and temporal references, hindering reliable comparisons.
• Qualitative scope: The interview study, while diverse across roles and countries (DE, DK, GR, UK), is exploratory and qualitative, limiting generalisability.
• Pilot evaluation constraints: Pilots involved relatively small samples and subjective usability ratings (e.g., Hellenic Red Cross managers n=5 for detailed usability medians); quantitative impacts on recovery rates/times were not rigorously measured or reported.
• Policy heterogeneity: Ongoing variability across EU member states and evolving legal contexts (e.g., post-Brexit arrangements) limit the uniform applicability of findings and the solution’s integration with authorities.
• Outcome evidence: Although the solution has been used in over 85 cases, detailed outcome statistics (e.g., time-to-recovery improvements, clearance rate changes) are not provided in this article.