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Review of the characteristics of human trafficking and anti-modern slavery interventions and policy


Modern slavery refers to slavery, servitude, forced or compulsory labour and human trafficking, as defined by the United Kingdom’s (UK) Modern Slavery Act 2015 (Modern Slavery Act, 2015: c.30, 01). Victims of modern slavery face exploitation and human rights violations. Modern slavery is a well-hidden crime within which there are many types of perpetrators who face high profit and low risk in many countries (Walk Free Foundation, 2018). It is estimated that in 2013, there were 10,000 – 13,000 potential victims of modern slavery in the UK alone (Annual Report on Modern Slavery, 2018: 08). However, it is likely that there are in fact many more victims of modern slavery than estimated, considering that it is often run by organised crime networks and many victims are incapable of or unwilling to report crimes against them.

This review aims to describe the prevalence and characteristics of modern slavery in the UK, current interventions aiming to prevent modern slavery and provide support to victims, and the effectiveness of current interventions.


Aims and Objectives

This review aims to answer the following research questions: ‘What are the characteristics of human trafficking in the UK?’, and ‘What interventions are involved in combating the issue?’. The objective of the review is to provide an overview of modern slavery in the UK and contribute to the body of knowledge on this subject.

Literature Search

A desk-based review of published and peer reviewed studies as well as grey literature on modern slavery and human trafficking in the UK was conducted. Studies were identified through internet searches. To be included in the review, studies and reports had to be written in English, published after the year 2000, report characteristics of human trafficking processes, forms, perpetrators, and/or victims in the UK or describe the components and outcomes of policies or interventions designed at preventing human trafficking or providing services to victims of human trafficking in the UK. A study/report was excluded from the review if it was written in another language other than English, published before the year 2000, or did not focus on the characteristics of human trafficking in the UK or components or outcomes of human trafficking-focused policies or interventions in the UK. A title and abstract screening was undertaken at which point inclusion and exclusion criteria was applied.

Data Analysis

A thematic analysis (TA) approach was used with the aim of identifying and assessing patterns, or ‘themes’ that emerge through the existing literature. Data was categorised according to whether it reported prevalence, characteristic, intervention component, or intervention outcome. Themes which emerged through the literature allowed the researcher to identify issues which are shared amongst a wider group, for example the difficulty obtaining accurate figures of modern slavery victims. The data collected from various literature was then organised into categories in accordance with the themes identified. In order to give readers a better understanding, specific examples were used in some instances, for example the typology of perpetrators of modern slavery and trafficking.

State of the Literature

Literature on modern slavery and human trafficking in the UK describes a variety of forms of enslavement, such as forced labour, bonded labour, debt bondage, child labour, sexual exploitation and trafficking, domestic servitude, and forced marriage. Much of the research available demonstrates the nature of, and the ways in modern slavery occurs in today’s society. Most literature is enslavement in the form of sexual exploitation, with less focus placed on labour exploitation and other types of exploitation/slavery. A majority of studies are qualitative and use secondary data, for example police reports or reports from non-governmental organisations (NGOs). Re-framing and of secondary data and the use of different definitions of trafficking by agencies, organisations and countries leads to difficulty in obtaining accurate facts and figures surrounding the topic.

Characteristics of Modern Slavery

Prevalence of Modern Slavery

It is estimated that in the United Kingdom in 2018, 136,000 people were exploited in different forms of modern slavery, with the estimated proportion of the population to be living in modern slavery to be 2.08 out of 1,000 people (Global Slavery Index (GSI), 2019). In 2017, the National Referral Mechanism (NRM) documented 5,145 reports of potential victims of modern slavery, a 35% increase from 2016 (NCA, 2018: 01). Out of reported cases, 2,454 victims were female (47%) and 2,688 were male (52%), 3,027 (59%) were referred for adult exploitation categories and 2,118 (41%) were referred for exploitation as a minor (National Crime Agency (NCA), 2018: 05). Potential victim estimates put forward by the NRM are low in comparison to the Global Slavery Index (GSI) estimates, which highlights the difficulty in obtaining definitive figures of the issue. Differences in methodologies for measuring prevalence may also cause varying estimates. The GSI used secondary data combined with extrapolation from some eastern European countries where random sample surveys had been accomplished to provide an estimate of slavery in the UK at 0.013% of the national population, or approximately 8,300 individuals (Bales, Hesketh, Silverman, 2015: 18). Results also may vary due to changes in definitions implemented by the authors. For example, critics have stated that the GSI alters their definition of modern slavery each year which, in turn, makes comparing data more difficult (Gallagher, 2017: 91).

Differing definitions of ‘modern slavery’, ‘victim’, ‘exploiter’, ‘perpetrator’, and ‘trafficker’ is one reason why measuring modern slavery, especially across countries with different legal definitions and between agencies or organisations with their own unique operational definitions, is difficult. Challenges to data collection also include barriers to reporting that victims experience. Many victims may not understand they have been exploited. Victims are often afraid to report their experience to law enforcement, either fearing they will face punishment, due to migration status for example, or fear that their exploiters will retaliate. These ‘micro’ factors inhibiting accurate reporting and data collection are often a result of the social and cultural phenomena related to the types of exploitation in a community, city, and country; as well as broader environmental factors. The types and forms of exploitation and resulting impact on victims’ ability and willingness to report their own exploitation are vastly different from the majority of victims’ experiences in the United Kingdom to those in South Asia, for instance.

Evidence of modern slavery in the UK consists of a lot of gaps, and while estimates are based on cases that have been made known to the authorities, the figures likely underestimate the true scale of exploitation. This prevents policymakers and practitioners from achieving a complete understanding of modern slavery and from developing effective interventions to tackle the issue.

Victims of Modern Slavery

Britain is both a source and destination country for victims of modern slavery, with rising numbers of British citizens being identified as victims of modern slavery (Independent Anti-Slavery Commissioner, 2019). Potential victims of modern slavery and exploitation who are UK nationals has increased by nearly 100% since 2017, from 820 referrals of potential victims (UK nationals) in 2017 to 1,625 referrals in 2018 (NCA, 2019: 01). Potential victims can be adults, children, male or female. The NRM end of year summary for 2018 notes the number of victims of modern slavery reported was 6,993 (a 36% increase from the previous year) which comprised of 2,728 females (39%), 4,261 males (>60%) and 4 recorded as transgender (<1%), 3,856 (55%) referred as adults and 3,137 (45%) referred as a minor (NCA, 2019: 05). These statistics were made up of victims from 130 different countries; the top three countries being the UK, Albania and Vietnam (NCA, 2019: 01).

Common risk factors include poverty, poor educational attainment, a lack of cultural and/or social capital, and homelessness. Many victims have already faced abuse in their life, including childhood sexual abuse. Generally, victims of modern slavery are often recruited when highly vulnerable (for example when battling a substance addiction or homeless) and when they display low self-esteem, poor judgement, neediness and lack of support systems (Slavin, 2002). These characteristics allow for manipulative predators to gain the trust of their victims. Exploiters may claim they will ‘protect’ and