San Francisco - The Electronic Frontier Foundation (EFF) urged the high court of Massachusetts today to protect the rights of passengers in cars that law enforcement are tracking with GPS surveillance technology, arguing that both the driver and the passenger of a car have legal standing to challenge the collection of sensitive location data gathered by the GPS devices.

In Commonwealth v. Rousseau, police obtained a search warrant to install a GPS device on a car owned by a suspect in a number of arsons throughout the state. Ultimately, the owner of the car and his frequent passenger – Rousseau – were charged with a number of crimes, but both moved to challenge the search warrant. They argued that the police had made material misrepresentations in obtaining the search warrant, and as a result the GPS evidence should be excluded from the trial.

Although the trial court agreed that police had misrepresented the facts in order to get the search warrant, it upheld it anyway. Additionally, the court found that Rousseau had no legal ability – or standing – to challenge the GPS evidence because he was merely a passenger. But in an amicus brief filed today, EFF argues that critical privacy questions affect everyone who is traveling in a tracked vehicle, and they should all have the opportunity to protect themselves and their location data, whether they are a driver or passenger in the car.

"Location data communicates a huge amount of personal information to law enforcement," said EFF Staff Attorney Hanni Fakhoury. "Where you go throughout the day could point to your religious affiliation, who your family and friends are, your medical conditions, and your political leanings. It's only fair that everyone who is caught up in this extraordinarily invasive surveillance has the right to contest its gathering and use, particularly when that evidence is used by the state to try and throw someone into jail for decades."

Police are increasingly employing persistent locational tracking – through GPS, cell phone records, or other, more aggressive tools like cell tower dumps and "stingrays" – as part of routine criminal investigations. As this kind of evidence-gathering becomes more widespread, it's important to ensure that individuals who are targets of the data-collection dragnet have the legal right to challenge whether the surveillance has been done properly.

"The idea that you lose your right to challenge the use of invasive technology designed to track your location simply because you were in the passenger seat of a car rather than the driver's seat is ludicrous," said Fakhoury. "Giving police this sort of windfall based solely on which car seat a person is in ignores the reality that everyone has an expectation of privacy in their movements, and it only encourages police to aggressively gather a digital dossier of someone's movements. Proper court oversight is necessary to protect the Fourth Amendment, and that's all we're asking for here."

Thanks to Kit Walsh at the Cyberlaw Clinic at Harvard Law School's Berkman Center for Internet and Society for assistance with writing and filing the brief.

For the full amicus brief:

https://www.eff.org/document/amicus-brief-15