These briefings are based on the research project, "Statistical analysis of the National Referral Mechanism" led by the International Organisation for Migration.
The research was funded by the PEC which in turn is funded and supported by the UK Arts and Humanities Research Council (AHRC). The Modern Slavery PEC have actively supported the production of this Research summary. However, the views expressed in this summary and the full report are those of the authors and not necessarily of the funders.
Statistical analysis of the National Referral Mechanism (NRM)
These briefings will offer new analysis of NRM statistical data that aim to improve understanding of the nature and scale of modern slavery, including information on referrals and how changes in policy and legislation impact the statistics.
The first briefing has now been published, you can find more information here:
Research team: Dr Patrick Burland (IOM UK) Yiwen Zhang (IOM UK)
Briefing one
Seeing beyond the negative
An examination of key variables in the different reasons for the decisions not to formally recognise people as survivors of modern slavery.
Published: 6 November 2025
Background
This briefing explores the different reasons for negative Conclusive Grounds (CG) decisions from the National Referral Mechanism (NRM) (the UK’s system for formally identifying and supporting victims of modern slavery) for people referred between 2020 and 2024. A negative CG decision means that the person is not recognised as a victim of modern slavery by the UK government and thus not eligible for modern slavery protections in the UK which give effect to the 2005 Council of Europe Convention on Action Against Trafficking in Human Beings (ECAT). When an individual receives a negative CG decision, they have up to fourteen working days of move-on support before they fully exit the support provided through the NRM.
The briefing provides the findings of quantitative analysis of the publicly available disaggregated UK NRM data on potential victims of modern slavery from the UK Data Service (UKDS).
A focus on negative CG decisions is important at a time when more people than ever (both in absolute and percentage terms) are receiving a negative CG decision. 2024 saw a record 7506 negative CG decisions, an increase of 1067% compared to 643 such decisions in 2022. In comparison, positive CG decisions in 2024 increased by 77% compared to 2022. In 2024, 44% of CG decisions were negative compared to only 10% in 2022.
Key Findings
- Decisions made by the Immigration Enforcement Competent Authority (IECA) have a higher likelihood of receiving a negative Conclusive Grounds (CG) decision compared to the Single Competent Authority (SCA), and cases decided by IECA are 2.67 times more likely to receive a negative CG decision for insufficient information (more information on the two competent authorities follows in below sections).
- People referred to the NRM by a Government Agency were 1.53 times more likely to be given a negative CG decision for insufficient information compared to non-governmental organisation (NGOs) and third sector organisations.
- Cases that were recorded as "domestic exploitation” were 1.52 times more likely to receive a negative CG decision for the reason of not met the definition compared to those not recorded as domestic exploitation.
- "Not specified or unknown" was the fourth most recorded type of exploitation between 2020 and 2024 after criminal exploitation, labour exploitation, labour & criminal exploitation.
- For males, there is a 78% increase in the likelihood they will receive a not credible CG decision, compared to female referrals.
- Adults referred to the NRM were eight times more likely to receive a negative CG decision for the reason of not credible compared to children.
The analysis finds that the variables of Albanian and Vietnamese nationality were more likely to get a negative CG decision recorded as not credible and less likely to get a negative CG decisions on the grounds they had not met the definition or because there was Insufficient information to meet the standard of proof required.
Key Recommendations for the Home Office
For the first responder National Referral Mechanism identification process
Assess the capacities of government agencies to submit high quality NRM referrals and to provide the competent authority with further information as required (including considering requests for extensions for additional time to provide such information). Follow up with providing training and capacity building as required.
Amend the NRM referral form to allow for “at risk of sexual/labour/etc exploitation” to be selected.
Provide training to first responders on how exploitation type is recorded to ensure that the existing options of sexual/labour etc are appropriately utilised.
The Home Office/Forced Marriage Unit could design and deliver training for First Responder Organisations on forced marriage and domestic servitude and how to signpost such cases to the Forced Marriage Unit and other forms of support and assistance.
For the formal National Referral Mechanism identification process
Revisions to the Statutory Guidance which increase the requirements for steps that decision makers must take to obtain evidence, and strengthen the opportunities for individuals and their representatives to provide evidence before a decision is made.
Identify ways for improving information sharing for cases where people are in prison or immigration detention.
Amend the section on evidence gathering at CG stage in the Modern Slavery Act Statutory Guidance to recognise and address the specific challenges for people in prison or detention to provide evidence. This could include the policies on timelines to respond to requests for evidence, and specifically including people in prison or detention to the list of examples where extension requests may be granted.
Re-establish a Single Competent Authority.
Update the Statutory Guidance to more broadly address issues affecting disclosure for males which could impact their credibility.
Further scaling up devolved decision-making panels for children referred to the NRM which have been piloted across thirty local authorities in England, Wales and Scotland and explore what such a model could look like for adults referred to the NRM.
