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Insight

What actually happens when CBP detains your shipment

19 August 2026

Almost everything written about forced labour describes the regulation. This describes what happened to a company that lived it: four containers detained, and documentation that turned out to be legally impossible to obtain.

Most compliance programmes rest on a reasonable assumption: that if you are asked for documentation, you can get it. It may take time, it may take insistence, but eventually the supplier sends it.

This is an account of what happens when that assumption fails. It is based on the experience of a supply chain compliance director at a US public company, told in the first person. Names and identifying details are omitted.

The detention

Four containers of motors manufactured in China. US Customs detained them, and for the first several days no explanation arrived. Then came the form: the authority had invoked the forced labour protocol.

They will ask you for the dog's birth certificate.

The questions reached far past the direct supplier. How the product was made, in which city, how that supplier manages its own suppliers, how it ensures the second- and third-tier suppliers are not involved in prohibited practices, and where every material on the bill of materials came from.

In other words: the authority did not ask about the supplier. It asked about the supplier's supplier's supplier.

The problem no compliance programme anticipates

This is where the case stops being a paperwork story and becomes something else.

Chinese suppliers are prohibited by law from providing that information. It was not that they were unwilling to cooperate, or that the data was hard to assemble. The instruction from the local government is that a supplier shares nothing beyond what is strictly necessary for the commercial transaction. Sharing their bill of materials, naming who they buy from, or disclosing whether they conducted forced-labour screening, is forbidden.

The documentation the US authority demanded was, for that supplier, legally impossible to hand over.

No contractual clause solves that. No annual letter signed under penalty of perjury solves it. The compliance programme was built on the assumption that the information exists and can be requested — and that assumption broke.

What they tried

First, specialist US trade lawyers. The result, in his words:

They just took our money. They were as much in the clouds as I was; I knew more about forced labour than they did.

Then, reverse engineering. If the supplier would not provide its bill of materials, they reconstructed it. Their engine experts listed what is required to build one: crankshafts, blocks, pistons, heads, cylinders, rings. With that list they licensed a supply chain intelligence tool and began tracing which companies produce those components and which have forced-labour histories.

They got a long way. It still was not enough to satisfy what the authority had asked for.

How it ended

They wrote to Customs requesting authorisation to export the containers. They would not use the material, they could not comply with the request, the supplier would not respond, and meanwhile demurrage and detention costs were accumulating.

The authority agreed. Two weeks to get the goods out of the country. They moved them to a bonded facility, completed the formalities, and re-exported.

That outcome is no longer available. Under current policy, detained goods cannot be re-exported: they are forfeited and remain in Customs custody until the requirements are met. And if the authority determines the company has forced-labour connections, nothing is ever released.

The exit that saved those four containers would not exist today.

Three things this case teaches

1. The question is not about your supplier

It is about the origin of materials, several tiers upstream. A programme that covers tier-one suppliers — which is most programmes — does not answer what the authority actually asks.

2. The clock starts at detention, and by then it is late

Thirty days to assemble documentation that would take months to obtain in the best case, and cannot be obtained at all in the worst. Any evidence file that begins when the container is already held began too late.

3. Companies do not react until it happens to them

The most honest line in the entire conversation was this:

Companies do not react voluntarily until something happens to you. It happened to us.

And when asked whether, knowing what he knows now, he would have bought the tool earlier:

If I could start again, I would have acquired it long before, to be preventive rather than reactive.

What to do with this

There is no comfortable conclusion. Second- and third-tier documentation is difficult to obtain and, in some jurisdictions, impossible. What is within your control is this:

None of that prevents a detention. What it determines is whether, when one happens, you lose the goods or you lose considerably more than that.

Start with what you already have

If your suppliers send you an annual letter declaring they do not use prohibited labour, check one against the standard. Most cover two or three of the ten elements expected. Free, English or Spanish, scanned documents work.

Check a letter