Image: Warehouse loading dock exterior view, licensed under CC0 1.0.
A carrier bills you 4.5 hours of detention at a Dallas cross-dock. The rate on the line matches your contract to the cent. Your team approves it, because the rate is the only thing anyone is actually in a position to check.
That approval is the problem. Detention is not a pricing question. It is an evidence question, and a correct rate tells you nothing about whether the delay happened, how long it really ran, or whose fault it was.
Four claims hiding in one line item
Every detention charge asserts four separate things at once, and each one can fail independently:
- The driver arrived at a particular time.
- The driver departed at a particular time.
- The gap between the two exceeded the free time your contract grants.
- The excess was your facility's doing rather than the carrier's.
Rate matching tests none of them. It confirms that if 4.5 billable hours occurred, the price for those hours is right. The conditional carries the entire weight of the charge, and nothing in a standard audit ever examines it.
The money involved is not trivial. A 2018 report from the U.S. Department of Transportation's Office of Inspector General estimated that detention reduces annual earnings for for-hire truck drivers by $1.1 billion to $1.3 billion, and found that a 15-minute increase in average dwell time at a facility raises the expected crash rate by 6.2 percent. Detention is a real operational cost with real safety consequences. That is precisely why the charge deserves to be proven rather than assumed.
Ocean fixed the paperwork problem. Road never did.
Containerised freight went through this argument already and came out the other side with a rule. The Federal Maritime Commission's Demurrage and Detention Billing Requirements, effective May 28, 2024, obliges carriers and marine terminal operators to put a specified set of data elements on every demurrage or detention invoice, and to issue it within 30 days. Leave a required element off and the billed party has no obligation to pay the charge at all.
Road detention has no equivalent. A motor carrier can bill you for dwell with a start time, an end time and nothing else, and the invoice is perfectly valid. Whatever evidentiary standard applies to truck detention is the one you impose yourself, in your own audit, before the payment goes out.
The evidence chain, in order
Arrival and departure
Geofence crossings from your visibility provider give you both timestamps independently of the carrier's own record. Where the two disagree by more than a few minutes, the disagreement is itself the finding. A driver who logged an arrival 40 minutes before the tractor entered the geofence has billed you for 40 minutes of interstate.
Free time
Free time is contractual, and it varies by lane, equipment type and facility. Two hours is the common figure, but a drop trailer arrangement may grant none at all, because none is needed. Recomputing the billable window against the clause that actually governs the shipment, rather than against a house default, is where a surprising share of detention quietly disappears.
Causality
This is the test almost nobody runs, and it is the one that decides the charge. A driver who shows up three hours outside the appointment window and then waits has not earned detention, because the wait follows from the late arrival. Neither has a driver who arrives without the paperwork the receiving dock requires, or with a trailer the facility cannot work. The clock ran in every one of those cases. You were not the one who started it.
Why sampling cannot close the gap
Detention is individually small and collectively enormous, which is the worst possible shape for a sampled audit. Reviewing one invoice in eight will catch a duplicate or a rate error, because those are visible on the face of the document. It will not catch a causality failure, because the evidence that would expose one lives in telemetry and appointment records the auditor never pulled.
So the charges that survive a traditional audit are the ones that look correct on paper. That is a selection effect, not a clean bill of health. Post-payment recovery has the same blind spot, arriving months later, when the timestamps are cold and the carrier relationship makes a short pay expensive in ways the spreadsheet does not show.
What Penny checks before the invoice clears
Penny audits every freight invoice before payment rather than sampling after it. On a detention line she pulls the geofence trace and the trip stop record, recomputes the billable window against the specific contract clause governing that lane and equipment, and then asks the question the rate check skips entirely: is this delay attributable to us at all?
Where the charge holds up, it clears without anyone touching it. Where it does not, she drafts the dispute with the timestamps, the clause and the causality finding already attached, so the carrier conversation opens with evidence instead of a short pay nobody on either side can explain.
| Check | Rate matching | Pre-payment audit |
|---|---|---|
| Price matches the contract | Yes | Yes |
| Arrival and departure verified independently | No | Geofence and trip stops |
| Free time applied per governing clause | House default | Per lane and equipment |
| Delay attributed to a cause | No | Yes |
| Coverage | Sample | Every line |
| Timing | After payment | Before payment |
Where to start this month
You do not need a platform to run the first pass. Take last month's approved detention charges and pull the geofence trace for each one. Compare billed dwell against observed dwell, then check how many of the surviving delays began with an arrival outside the appointment window.
Most teams find the gap is not in the rates at all. It sits in the hours nobody was ever in a position to question, on invoices that passed every check anyone thought to run.
Book a walkthrough to see Penny run this evidence chain against your own detention charges.