This has been coming for months, but yesterday California governor Jerry Brown signed a new law that requires all smartphones sold in the state after July 15 to have a kill switch that owners can use to remotely wipe stolen phones of personal data and make the phone unusable to discourage petty theft and make identity theft a bit harder.

Wireless Association Mobile kill switch

Kill switch: Smartphone theft on the rise nationwide

Most mobile OS have supported some sort of kill switch, but they have relied on users opting in or installing specific apps, so most people would only become aware that the option existed after their phone had been stolen. By requiring the kill switches to be installed before they are sold, and then giving consumers the option to opt out, they are a lot more likely to be available if you want to use them.

As smartphones have become more powerful and more expensive, they have become more attractive targets for thieves. Consumer Reports found that smartphone thefts doubled from 2012 to 2013 to more than 3.1 million incidents, and California state senator Mark Leno, one of the laws main advocates, has said that two-thirds of robberies in San Francisco and a quarter in Oakland involve smartphone theft.

Mandatory kill switch may not deter theft

Early on, tech companies criticized the new law because they argued that the technology wouldn’t really work and that it would make phones more expensive. While most companies eventually changed their stance, perhaps realizing which way the momentum was headed, it’s not clear that this will really dissuade anyone from stealing smartphones. Wiping personal data is a great way to protect people from being re-victimized after the mugging, but bricking a phone with software is reversible. Since consumers will have the option to unlock their phone by entering a pin, it’s only a matter of time before someone figures out how to hack the locked phones. Apple Inc. (NASDAQ:AAPL) iPhones may be more secure since the software that can run on them is highly vetted, but phones that run Google Inc (NASDAQ:GOOG) Android will probably just have a new version of the OS installed and then be sold as used.

The other danger is that the kill switches will be abused. If law enforcement had the opportunity to erase data and brick smartphones in Ferguson over the last few weeks (the same smartphones that were used to record officers threatening to shoot people and other abuses), they would have. Installing technology that makes that possible into everyone’s phones means that it will eventually be used.