California’s cell-phone kill switch is a solution that’s worse than the problem

As the California legislature moves to mandate “kill switches” that will allow owners of stolen phones to shut them down, the Electronic Frontier Foundation sounds an important alarm: if it’s possible for someone to remotely switch off your phone such that you can’t switch it back on again, even if you’re physically in possession of it, that facility could be abused in lots of ways. This is a classic War on General Purpose Computation moment: the only way to make a kill-switch work is to design phones that treat their possessors as less trustworthy than a remote party sending instructions over the Internet, and as soon as the device that knows all your secrets and watches and listens to your most private moments is designed to do things that the person holding it can’t override, the results won’t be pretty.

There are other models for mitigating the harm from stolen phones. For example, the Cyanogen remote wipe asks the first user of the phone to initialize a password. When it is online, the device checks in with a service to see whether anyone using that password has signed a “erase yourself” command. When that happens, the phone deletes all the user-data. A thief can still wipe and sell the phone, but the user’s data is safe.

Obviously, this isn’t the same thing as stolen phones going dead and never working again, and won’t have the same impact on theft. But the alternative is a system that allows any bad guy who can impersonate, bribe or order a cop to activate the kill-switch to do all kinds of terrible things to you, from deactivating the phones of people recording police misconduct to stalking or stealing the identities of mobile phone owners, with near-undetectable and unstoppable stealth.

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