You buy a car, but the data stream you have to have in order to be able to diagnose what's wrong with it – in order to be able to repair it – is not owned by you. At least, that is the position taken by the vehicle manufacturers, collectively. They insist that while they are ok with you being allowed to physically possess the vehicle, they get to decide who gets to repair it – by restricting who can access the data stream necessary to diagnose what's wrong with it.

They have asserted this right control repair by asserting that only they – via their proprietary diagnostic equipment – may access the data stored in and transmitted by what they implicitly consider to be their vehicle. They have asserted this by preventing the owner – or should it by styled the possessor – from having access to the data generated by the vehicle. This effectively forces you to come to them – to their authorized dealers – when the vehicle they allow you to possess (and to pay for) needs fixing.

Even independent mechanics cannot diagnose – and so are unable to fix – certain makes/models that are "sealed" to them, too – because they do not have the authorized proprietary equipment to to open them up. They can raise the hood of course – but only to look.

They might as well just leave it down.

Enter what are styled right to repair laws. These are laws that say you – the person who paid for the vehicle and any other person you authorize – have a right to know what's wrong with your car, in order to be able to repair it yourself. Or have it repaired by someone other than an "authorized" (by the manufacture of your vehicle) dealer. A case in Massachusetts was just decided that says the person who owns the vehicle has the right to access the data necessary to repair it. More finely, the vehicle manufacturers – that's plural, so all of them – have no right to lock the owner or his chosen mechanic out of the vehicle, by denying then access to the data that is needed to diagnose and repair it.

Judge Denise Casper dismissed a challenge by the vehicle manufacturers' oddly named lobbying entity, the Alliance for Automotive Innovation, that asserted only the vehicle manufacturers or their authorized dealers have the right to that data because otherwise "people" might tamper with or even defeat emissions controls (specifically, the programming that controls a late model vehicle's emissions control systems).