Last year, Tesla’s Model 3 famously fell out of the good graces of Consumer Reports for having lousy brakes. “The Tesla’s stopping distance of 152 feet from 60 mph was far worse than any contemporary car we’ve tested and about 7 feet longer than the stopping distance of a Ford F-150 full-sized pickup,” wrote the reputable institution. Days later, Tesla CEO Elon Musk vowed that the problem would be fixed immediately over-the-air. “Firmware fix for upgraded brake performance on standard Model 3 started rolling out yesterday,” Musk promptly tweeted.

There has been a lot of speculation as to why other OEMs aren’t doing Over The Air Updates [OTA] the way Tesla does. Are they daft? Or are they greedy for the update money made in the shop? After diving deep into the topic, I have come up with a surprising reason: OTA, the way Tesla appears to be doing it, is illegal in many, if not most parts of the world.

Author's note: This report is based on several interviews with experts in the field. Due to the sensitivity of the issue, and its political aspects, all experts have requested anonymity.

A few days thereafter, Consumer Reports could happily report that it “now recommends the Tesla Model 3, after our testers found that a recent over-the-air (OTA) update improved the car’s braking distance by almost 20 feet.” That was fast.

The feat was feted in a Tesla-happy media as a triumph of genius mind over mechanical matter. It also caused hairs to stand on end among automobile engineers around the world. How could a significant change to the characteristics of a safety-related item such as the brakes possibly be developed, tested, verified, and documented in a matter of days, the engineers asked. And how in the world would Tesla at such short notice plan to receive the type approval necessary in most developed parts of the world (outside of the U.S. and Canada) experts at OEMs from Europe all the way to India, China, and Japan tsk-tsked.

The consensus was that in the U.S., the miraculous over-the-air brake improvement was at the very least a risky operation that could attract the attention of the regulator. Performed in the rest of the developed world, it would mostly be illegal, I am told. (The Model 3 was available only in the U.S. at the time, and not in big numbers.)

A full appreciation of the illegality requires some understanding of the type approval regimes around the world. Here is the capsule version:

In most parts of the world, an automobile must be road legal to be fit for sale. In the business, this is referred to as “homologation." In the U.S. and Canada, the OEM certifies that the vehicle complies with all rules, such as FMVSS in the U.S., or CMVSS north of the border, along with other voluntary agreements such as NCAPs and more, and the car is good to go. OEMs must have all tests and documentation done in case the authorities come checking. Nobody really worries a lot what is done to the car once it’s off the lot.

In Europe, India, China, Japan, and many other countries, compliance with the rules must be demonstrated to the authorities. If the regulators are happy, they issue a “certificate of conformity” with the rules. This CoC, often nicknamed the “birth certificate of the car,” is the basis of the type approval, and it allows the car to be sold and operated.

Type approval regimens differ between countries. The EU has one set of rules, called WVTA, or “Whole Vehicle Type Approval.” WVTA is accepted in many countries outside the EU, also in the way of trade agreements. Other countries have their own rules, but all of them mostly draw on a set of 100+ United Nation rules, just like the electrical code in an American town draws on NFPA70, the U.S. electrical code.

And now it is getting interesting. One of the core tenets of these UN rules is that once type-approved, components or systems may not be changed unless there is a new, or updated type approval. Why? Because the changed component would not be the same as the type-approved one. The component may not be changed by the OEM before the car is sold, AND the component may not be changed by the customer AFTER the car was sold. This doesn’t stand in the way of technical progress: A changed component can be brought into compliance with a new or amended type approval.

As an upstanding American, you will likely protest: “You are putting me on. Where I live, I can do to my damned car whatever I damned please. If the gas station down the road gives me the sticker, I’m good.”

Call yourself blessed. In the rest of the world, you wouldn’t be so lucky.

In the case of the updated Tesla brakes, the over-night change of performance, performed in Europe for instance, could lead to a loss of the type approval for the whole car. The EU adopts UN Regulation 13-H, which is the applicable brake regulation. Reg 13-H demands that “a vehicle approved to this Regulation shall be so manufactured as to conform to the type approved.” It furthermore specifies that “the approval granted in respect of a vehicle type pursuant to this Regulation may be withdrawn if the requirements laid down in paragraph 8.1. above are not complied.” You will find similar language in all the pertinent UN rules. Sorry, no change.

The upshot of all that legalese is that in all countries subscribing to these UN rules, and that’s pretty much everywhere outside the U.S. and Canada, any changes to type-approved components and systems may result in a loss of type approval if the changes are made without a new or updated type approval. An that means any changes, whether mechanical or electrical, analog, or digital, by hand, or over the air. To update that change of brake performance on cars exported to Europe for instance, Telsa would have to find a technical service that tests, documents, and certifies the performance characteristics, and then its Dutch regulator would have to issue a new, or amended type approval good for all of the EU, experts at various OEMs tell me to a man and woman. For countries that do not automatically accept an EU WVTA , additional steps would be required.

If you have followed this so far without your eyes glazing over, you probably will ask: “What’s keeping the daft and greedy OEMs from doing OTA if they have the damned approval?” Well, many regulators simply don’t like OTA updates at all, except for stuff like the entertainment and navigation systems. They prefer that the update is made in the shop, where the problem can be fixed in case the updated component is bricked.

But whoa, will you ask, Tesla Model S and X have been exported to many countries, including the EU, with OTA, and why is nobody creating a stink?

When I put that question to my panel of anonymous experts at various OEMs, much eye-rolling ensued. “They are such a young company,” I heard. Does nobody raise the issue for fear of hitting a baby? Well, yes, I was told, and it’s bad PR to be the grinch. Occasionally, software changes performed at the shop also don’t come with the requested paperwork, conceded a candid correspondent, “and nobody wants to rock the apple cart.” Nevertheless, Tesla runs a the considerable risk of business disruption should a severe accident lead to the surprising revelation that a type-approved vehicle was changed without the proper permits.

Tesla won’t have OTA all by itself in the future. Probably prodded by the Californians, stakeholders around the world have been discussing since 2016 how to bring the wild-west OTA in compliance. Draft regulations are floating around, and a subcommittee working on pilot tests will meet next week in Paris. A final regulation that would make OTA acceptable in regions subscribing to the UN ruleset is possible (but not likely) by the end of 2019. At that point, countries and regions would have to adopt the new regulation (along with another one pertaining to cyber security) into their laws. Realistically, this is unlikely to happen before 2021, most experts opined.

A new OTA regulation would not automatically mean that OEMs can willy-nilly send updates without the proper paperwork. It is widely expected that the final OTA UN regulation will continue the requirement that type-approval relevant updates need an updated type approval. “Manufacturers should be required to submit relevant documents to the approval authority/technical services from the requirement analysis phase to the implementation phase,” a position paper circulated among OTA stakeholders states. The OTA regulation may even make future type approvals more complicated and take longer. If, for instance, the software change improves the render quality of a LIDAR system, it would affect the performance of braking and steering, says the paper, and it concludes that “the highly coupled nature of automotive subsystems would require software updates/changes to be considered not as standalone/retrofit changes but as complete system changes, which requires impact analysis studies on the effect of the changes.”

While I had their ear, I asked my panel of experts whether they are too stupid to update a vehicle over the air. “Of course not,” they answered to no-one’s surprise. Wireless is not much more involved than via a cable. Of course, the vehicle must be equipped with the proper interface. Expect OTA to appear in new models soon on a test basis, and en masse after the new regs are in effect.

Now what about the shops? Won’t dealers be opposed to losing service revenue, and the opportunity to sell us a “new set of rotors now that the car is in the shop?” That was - after all, we were off the record – readily conceded. The benefits of OTA would far outweigh the lost, I heard, and with a few smiles, it was suggested that with OTA, OEMs could now charge customers directly for upgrades, just like Tesla does.

You’re asking for Tesla’s answer to the whole issue? Good question. I asked Tesla weeks ago for a comment “on the subject of post-homologation changes that could violate EU and UNECE rules unless properly papered.” Tesla’s spokesperson Danielle Meister asked for my deadline. I said Friday last week. No answer was received, neither before, nor after last Friday.