A minicab licence cannot describe a car that drives itself, so Britain wrote one that describes the person sitting in it instead

Every strange feature of what happened in London last Thursday comes from a single decision, and it is a licensing decision rather than a technical one.

Transport for London did not license fifteen autonomous vehicles. It licensed fifteen private hire vehicles, with private hire drivers, operating under a private hire operator. Three permissions, all from a regime built in an era when the presence of a driver was the least interesting thing about a car.

Follow that through and the oddities stop being odd.

Why is there a person in every seat? Not because the technology needs one, necessarily, but because private hire law requires a licensed driver in a licensed vehicle. The law cannot conceive of the vehicle without them. So the person is there to satisfy a licensing condition, and whether the machine needs them is a separate question the licence does not ask.

Why is there no record of how often that person acts? Because a minicab licence has no concept of one. There is no field for it. The regime records who is licensed, what vehicle they drive, insurance, medicals, background checks. It was designed to establish that the person driving you is fit to do so. It has nothing to say about a machine handing control back, because when it was written that could not happen.

Why does nobody know when the seat empties? Because the answer lies in a different Act entirely. Section 83 of the Automated Vehicles Act provides that where an operator holds a permit, private hire law does not apply. That is the switch. Not a technical threshold, not a safety milestone, a legal one. The day a permit is granted, the requirement that put a human in the car simply stops applying to it.

So we have a service running under one framework while the framework that would govern it properly sits unused, waiting for a permission neither company has applied for successfully and neither will date.

What would an instrument actually look like, if somebody wanted one?

It would need three things, and none of them is exotic. A definition of the event: what counts as the machine giving up, distinguishing a technology fault from a driver choosing to act, which is precisely the ambiguity in the only documented London case. A denominator: miles or minutes driven in autonomous mode, so that a count means something. And a duty to file, with a consequence for not filing.

That is not a hypothesis. It is a description of what California has required annually since 2015, and it is not a sophisticated regime. It is a form, a deadline and a penalty.

Britain has the legislative machinery for this and is not using it. The Automated Vehicles Act exists. The permit regime exists. What does not exist is any obligation attaching to the current arrangement, because the current arrangement was licensed under something else.

There is a version of this that is entirely reasonable. Fifteen cars is a small trial. Loading a full reporting regime onto it before the enabling Act applies would be disproportionate, and the sensible answer may be that the data will arrive when the permit does.

The difficulty with that answer is the sequencing. The permit is the thing that removes the driver. So on the current arrangement, the country gets its first systematic evidence about whether the machine can be trusted alone at the same moment it stops requiring anyone to be there.

The evidence and the decision arrive together, which is a strange order to do it in.