Search, Seizure and GPS

Norman Sadeh

Norman Sadeh

The FBI tracks a suspected drug dealer via GPS secretly attached to his car. They arrest him with more than 200 pounds of illegal drugs and $850,000. He serves life in prison.

But did law enforcement violate his Fourth Amendment rights? Was their covert tracking without a search warrant intruding on a reasonable expectation of privacy?

This real-life case will be argued in front of the U.S. Supreme Court on Nov. 8, 2011. 

Norman Sadeh, Carnegie Mellon professor of computer science, offers his take on the case.

"Evolving technology is always changing the bar in this space and this case is just one instance," explained Sadeh, who contributed to a brief filed in defense of the defendant's rights. "GPS technology is a fully automated process with fine accuracy and almost-free hardware. You're talking about the ability to deploy this on a very large scale."

"If the Supreme Court were to rule against warrants for GPS tracking, the state of Pennsylvania could, for example, decide tomorrow that all license plates would be issued with a GPS monitor. It's actually economically practical today."

He added, "And this is just the surface. With GPS tracking you can collect trails of data that over time reveal a lot of very sensitive information, such as religious affiliation or medical ailments. By mining this data across populations you then discover social relationships, including marital infidelity, and much more."

Sadeh was tapped through his well-known work in the areas of mobile commerce and privacy. Years ago, his work with context-aware technology development and its need for information led him to question how people feel about the privacy implications.

"People's reasonable expectations of privacy do not allow for 24/7 GPS tracking with the level of accuracy that the technology entails," he explained. "Our findings can really help inform this case as it goes to the Supreme Court."

Importantly, where government leads, industry may follow.

"If it's OK for the government, industry will interpret this as a 'free for all'," said Sadeh. "It's very easy now for app developers to tap into your cell phone location. We've got tens and tens of thousands of mobile apps today that claim to need your location."

Related Links: Sadeh's page | Work by Sadeh and colleagues on location privacy | Brief [.pdf] | School of Computer Science

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