Modern Slavery and Human Trafficking: An Expanding UK Market

Unique threat: modern slavery and human trafficking connects to almost every other form of criminality impacting the UK. Image: motortion / Adobe Stock

This is the second in a series of articles on the top 10 serious and organised crime threats to the UK and their evolution over a decade. This article traces the journey of the threat posed by modern slavery and human trafficking, which has risen rapidly up the policy agenda over a decade.

Across the globe, supply chains of every description are tainted by exploited labour. The UK is no exception: here as elsewhere, labour is often the greatest cost to business. Reducing this cost offers the fastest route to increased margins. For some businesses, they will use whatever means possible.

The threat from modern slavery and human trafficking in the UK was already recognised at the advent of the National Crime Agency (NCA) – and, indeed, of its predecessor, the Serious Organised Crime Agency. While the maxim ‘the more you look, the more you find’ probably applies, it is likely that the exploited population has increased over 10 years. Referrals of potential victims through the National Referral Mechanism (NRM) have risen from 1,746 in 2013 to 16,938 in 2023 (the highest figure since the NRM began in 2009). And the threat is unique in that it connects to almost every other form of criminality impacting the UK – whether narcotics production and distribution, or industrial levels of fraud conducted on dating sites by enslaved workers.

The UK as a Market Opportunity

Modern slavery and human trafficking is far from a new crime. In 1860, a slave would sell in the US for the equivalent of around £30,000 in today’s money. In 2023, the price in the UK is often no more than the cost of the exploited person’s airfare.

Over the past 10 years, recruitment of victims has exploited the growing availability of social media. These platforms offer windows of opportunity for traffickers to tempt and trick, which they use with skill and alacrity. In many cases, traffickers then use these same tools to sell exploited services.

Back in 2014, the Home Office estimated that 10,000–13,000 people were subjected to modern slavery in the UK. While a revised official estimate is yet to be produced, today’s numbers are likely to exceed 130,000. The exploited sector is difficult to size, however. Victim testimony is hard to access and there are remarkably few prosecutions when set against the number of investigations conducted.

The UK consistently offers strong market opportunities for labour and sex exploitation. The risk of sanction is seen by offenders as manageable and modern slavery and human trafficking feature in the criminal delivery of most other organised crime threats. The operation of these market dynamics carries extraordinary latent risk to the UK and its institutions. The UK response must focus on disrupting the market fundamentals.

The UK remains poor at identifying revenues generated, which are probably significantly higher than existing estimates. In the case of commercial sexual exploitation, recent cases show that expected revenues per person could be around £20,000 per month. Labour trafficking – whether for cleaning cars, food production or care services – is modelled on significantly lower incomes, requiring a larger workforce to ensure profitability. Domestic servitude is potentially the most hidden of these crimes, with limited understanding of the revenues generated.

This decade, meanwhile, exploitation for the purpose of committing crime has become better recognised. This is often conducted to distance bad actors from their crimes, widen market access or launder criminal proceeds. Referrals of potential victims through the NRM related to county lines grew from just 1 in 2015 to 2,281 in 2022. Alongside this, today, is the wholesale exploitation of large groups in scam centres globally, preying on UK citizens in large numbers.

Market conditions dictate trafficking patterns. No trafficker recruits without strong confidence in their access to significant financial recompense. Traffickers often face churn in the exploited workforce – for example, due to law-enforcement action – and need a healthy pipeline of new recruits. These recruits may be tricked into enslaved conditions, by poor economic outlook (push factors) or a sense of opportunity (pull factors). The UK itself offers specific market-infiltration opportunities for traffickers in agri and food production, construction, and the care and service sectors. Demand for sex for money today massively outstrips the voluntary market.

While trafficking groups have always needed access to the financial system, they use it now more than ever to accept illicit payments

Brexit and a range of other factors are recognised to have impacted the market. While not fundamentally affecting the business model, there has been a change in the nationality profile of victims coming to the UK for ‘work’ of a kind considered labour exploitation. Polish and Baltic states victims are probably less prominent in 2023 than they were previously. And while victimisation of Vietnamese, Chinese and Filipino nationals remains consistent, adverts on adult services sites – among other evidence – point to an upswing in Romanian, Brazilian and Ukrainian victims.

Meanwhile, the advent of Covid-19 lockdowns had a significant impact on exploitative markets based on face-to-face activity, including in nail bars, gardening and household repairs. The sexual exploitation arena was also affected and many victims from other nations, together with their exploiters, headed home. Online, ‘camming’ activity bulged as many sought alternative sources of income. Markets recovered quickly once lockdowns eased – in some cases beforehand, indicating the strength of demand.

At the same time, a proportion of those secreted in vehicles and latterly small boats to the UK from northern France feeds demand for modern slavery and human trafficking. Of the 83,236 people arriving by small boat from 2018–22, 7% were referred to the NRM. This is a concern given growth in organised immigration crime, underpinned by changing migration patterns, over the past decade. A 2021 Home Office report showed that the prevalence of NRM referrals within the immigration detention system has increased in recent years.

Payment in cash for goods and services across the exploited sector is reducing compared with 10 years back. And while trafficking groups have always needed access to the financial system, they use it now more than ever to accept illicit payments. Retail Fintech institutions are increasingly popular, but the full breadth of the financial system is implicated. Revenues are likely to be significantly higher than existing estimates, with the cost to the UK estimated at £33 billion per year.

Analysing the Report Card – What Can We Learn?

A decade ago, modern slavery and human trafficking was not on the UK government’s agenda in any meaningful way. In the NCA’s 2014 National Strategic Assessment, ‘modern slavery and human trafficking’ did not exist as an ‘identified threat’ in its own right, as it does today. Instead, it was grouped together with – and described as a subset of – organised immigration crime.

Prioritisation and awareness have shifted significantly over a decade, however. Most notably, Theresa May as home secretary made action on this threat a ‘personal priority’. The inauguration of the office of the Independent Anti-Slavery Commissioner in 2014 has been an important development in this context. The recent appointment of the third commissioner is welcome, albeit overdue.

This growth in awareness has triggered legislative and enforcement action. Legislatively, the UK led the world with the passage of the Modern Slavery Act 2015. This stood out in particular for the adoption of Section 54 (Transparency in Supply Chains Clause), which brought the first vestige of accountability for company directors for exploitation in supply chains through the requirement to publish modern slavery and human trafficking statements.

Yet the same progress has not been sustained over time. Analysis of use of the legislation in practice reveals gaps in adherence, prompted by a low prospect of sanction and continued investor demand for higher margins. In particular, a downturn in businesses taking time to review and produce modern slavery and human trafficking statements per Section 54 appears to be an indication of reduced traction. That the necessary amendments to address the patchy impact of the law are floundering in Parliament is unhelpful to the effort.

On this point, the UK is now lagging behind. In Australia and Canada, issues around this legislation pattern have been addressed, while new human rights in business legislation in the EU has placed greater responsibility on business. In the US, The Uyghur Forced Labor Prevention Act and US Customs and Border Protection Agency’s ability to issue ‘Withhold Release’ orders for imported goods tainted by modern slavery are proving enormously impactful. The UK must catch up with the progress made elsewhere in recent years.

It is clear that the justice process cannot be the sole approach to tackling modern slavery and human trafficking

From a law-enforcement perspective, the UK investigative endeavour has been encouraging over the past 10 years. Despite this, the conversion rate to prosecutions is disappointing. High points include Operation Fort in the West Midlands, which identified more than 500 Polish victims exploited in the food, agri and timber sectors. The operation led to the conviction of key perpetrators, making it the largest successfully prosecuted modern slavery investigation in the UK. It also led to the emergence of the Modern Slavery Intelligence Network – a group of UK businesses and NGOs, linked to law enforcement, sharing intelligence and good practice.

More broadly, the adoption of the UN Sustainable Development Goals in 2015 and advent of the UN Global Compact – the world’s largest corporate sustainability initiative – have elevated debate around modern slavery in supply chains. Yet they have led to little real change thus far. The drive towards environment, social and corporate governance objectives has increased focus on the link between commercial success, profit and clean supply chains, but challenges remain in implementation and investment.

Meanwhile, the response to the proceeds of modern slavery and human trafficking (as indeed to other crimes) has left much to be desired. In 2011, the Financial Action Task Force – the global anti-financial crime standard setter – issued its first, somewhat rudimentary, advisory on the issue. Since then, results have been negligible, with very few Suspicious Activity Reports (SARs) predicated on modern slavery and human trafficking submitted – in the UK or internationally.

In the US, for example, of the 3.6 million SARs issued by financial institutions in 2022, only 5,798 appear to be predicated on human trafficking. In the UK, performance has been equally underwhelming, in terms of proportions of overall suspicious activity reporting. This is despite the 2015 promise by the European Banks Alliance – led by Thomson Reuters, Stop the Traffik, Europol and the newly formed Joint Money Laundering Intelligence Taskforce – to formulate usable red flags for modern slavery and human trafficking. Work in this area continues, but successes are rare and effective automation will be necessary to deliver progress.

Alongside this, the work of NGOs specialising in victim support has grown markedly in the past decade. Achievements include the integration of survivor experience into policy and practice. The charity-run UK Modern Slavery & Exploitation Helpline is well known and an important aspect of the response today. Yet the proliferation of different actors has created an increasingly disorganised response, with no clear policy on what roles should be played by whom.

Where Do We Go from Here?

It seems likely that the UK will remain a target for traffickers, while there remain strong market opportunities to exploit and little likelihood of being held to account. In this context, the Modern Slavery Act 2015 (Amendments) need to obtain statute status as a matter of urgency. The UK has – wittingly or unwittingly – given up its lead on the issue and needs to restate its resolve. Embarrassing cases will emerge to haunt politicians, officials and corporate actors and undermine the UK’s reputation if legislative change is left in the long grass.

In parallel, law enforcement must identify smarter routes to the prosecution threshold, in concert with the Crown Prosecution Service. Yet it is clear that the justice process cannot be the sole approach to tackling modern slavery and human trafficking. Instead, this must exist as an essential element of a wider mixture of responses.

To support this, the NCA and wider government policy teams should engage with economists and marketing specialists to more accurately account for shifting market dynamics. They should consider new evidence-based tactics, working with a range of partners to undermine market opportunities for modern slavery and human trafficking. Fundamentally, more work needs to be done to actively engage the NGO sector through meaningful joint working. Doing so would bear considerable fruit for law enforcement and policymakers.

The authors wish to thank Dr Bill Peace and Paul Studley for their support in the development of this article.

The views expressed in this Commentary are the authors’, and do not represent those of RUSI or any other institution.

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Neil Giles

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Cathy Haenlein

Director of Organised Crime and Policing Studies

Organised Crime and Policing

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