The state's existing law—which became the basis for new national standards implemented by the auto industry in 2014—required that vehicle diagnostic data was made available via an open platform. In short, that means that if you own a Toyota, you don't have to go to a Toyota-affiliated repair shop to find out why your "check engine" light is on. Any repair shop can plug a device into any car and read the data.

But the earlier law exempted wireless data transmitted via a car's telematics system. Increasingly, car manufacturers have been relying on telematics to transmit crucial data, potentially leaving independent repair shops in the dark. The new ballot initiative closes that loophole and requires wirelessly transmitted data to fall under the same open platform rules starting in 2022.

Even though there are "some genuine concerns that increasing access to a car's data could set the platform up for cybersecurity vulnerabilities," Reason's Scott Shackford explained last month, "that's an argument about being careful with technological development, not an excuse for depriving consumers of access to the data produced by the vehicles that they own."