Quick answer: Most public sector buyers collect modern slavery statements and consider the job done. That is not due diligence — it is paperwork. Real compliance means understanding what your suppliers actually do, where they source from, and whether anyone in that chain is being exploited.
The statement is the floor, not the ceiling
Under the Modern Slavery Act 2015, commercial organisations with a turnover above £36 million must publish an annual transparency statement. That threshold captures a reasonable slice of your larger suppliers. It does not capture your SMEs, your sub-tier suppliers, or the labour agencies your tier-one contractors use to staff a contract on a Tuesday afternoon.
So when a procurement team ticks "modern slavery statement received" and moves on, what have they actually established? That the supplier is big enough to have a legal obligation and has met it at the minimum level. That tells you very little about what is happening on the ground.
Where the risk actually lives
Modern slavery in public sector supply chains is not usually found in the boardroom of a FTSE-listed facilities management company. It is found further down: in the cleaning sub-contractors, in the agricultural supply chains for public sector catering, in garment manufacturing for uniforms, in the labour recruitment networks operating in sectors with high staff turnover and low wages.
The sectors that consistently carry elevated risk include cleaning and facilities management, construction, food production and catering, care and supported living, logistics and warehousing, and textiles. If you are buying in any of these categories and your due diligence consists of a statement on file, there is a gap.
What the Procurement Act changes — and what it does not
The Procurement Act 2023 raises the bar on supplier selection and ongoing contract management. Exclusion grounds, key performance indicators, the new transparency and debarment registers — these are all tools that create more opportunity to act on modern slavery concerns. The Act also brings a stronger focus on contract performance, which means buyers have better mechanisms to hold suppliers accountable throughout the life of a contract, not just at award.
What the Act does not do is think for you. The framework is better. The obligation to use it intelligently still sits with the contracting authority.
Due diligence that is worth something
So what does genuine engagement look like? A few things that I would expect to see from a well-run procurement function:
Risk-stratified approach. Not every contract carries the same exposure. A bespoke software development contract and a large catering contract are not equivalent risks. Your scrutiny should reflect that. Spend the time where the risk is.
Substantive supplier questions. Move beyond "do you have a statement?" Ask suppliers to describe their recruitment processes, how they check labour agency compliance, what whistleblowing mechanisms exist, and whether they have had any concerns raised in the past two years. The answers — and the confidence with which they are given — tell you something.
Sub-contractor visibility. A supplier's statement covers their own operations. It may say very little about who they use and under what conditions. Ask for sub-contractor disclosure, particularly in high-risk categories. Make it a contract condition, not a courtesy request.
Site visits and spot checks. For higher-value, higher-risk contracts, a desk review is not enough. Procurement teams and commissioning managers should have eyes on operational delivery at least occasionally. This is particularly relevant in care, construction, and FM contracts.
Reporting and remedy mechanisms. If something is identified, what happens? There should be a clear process — not a vague commitment to "take appropriate action." That means escalation paths, contractual remedies, and a willingness to terminate where necessary.
The Home Office guidance and UKRPSS
The Home Office publishes practical guidance on due diligence in supply chains. The Independent Anti-Slavery Commissioner has been clear that transparency statements without action behind them are not adequate. For buyers developing their supplier markets, the UKRPSS accreditation framework provides a structured way to assess supplier readiness across a range of compliance areas, including modern slavery.
None of these are perfect tools. They are, however, better than a filed PDF.
A note on proportionality
I am not suggesting that every district council needs a team of investigators. Proportionality matters. But proportionality means scaling your effort to the risk — not using resource constraints as a reason to treat compliance as an administrative exercise. Small teams can still ask better questions, use risk frameworks sensibly, and make contractual expectations explicit from the outset.
Practical takeaway
Review your highest-spend, highest-risk contracts in the categories above. For each one, ask: if something were happening in this supply chain right now, would we know? If the honest answer is no, you have work to do — and a modern slavery statement on file will not change that answer.