Should Law Enforcement's 'Stingray' System Track You Without a Search Warrant?

You've probably heard that law enforcement can geolocate you during a live call, but did you know the Feds can find you even if you aren't on your phone with a device called the "Stringray?"

The Wall Street Journal is reporting that a federal case against an alleged hacker has brought the capabilities of devices like the Stingray into the public eye.

The case has already spurred heated debate about the extent of our privacy and the protection against unlawful search guaranteed by the Fourth Amendment to the Constitution.

The Stingray is a generic term for devices that can track a cellphone's location as long as it is turned on. As the Journal described its method of operation, the Stingray functions by:

"mimicking a cellphone tower, getting a phone to connect to it and measuring signals from the phone. It lets the stingray operator "ping," or send a signal to, a phone and locate it as long as it is powered on."

Law enforcement across the country does not have a standardized procedure for obtaining permission to use devices like the Stingray, though generally police agencies obtain a court order and not a search warrant, which would require a higher standard of proof.

This raises the question: should law enforcement be able to know exactly where you are without going before a judge to show probable cause?

If your cell phone is sitting next to your bed, use of a Stingray would seem to be an electronic intrusion into the home akin to a search. That would mean, absent a search warrant, the device would run afoul of the 4th Amendment's protections against unreasonable search and seizure.

The case that has highlighted this issue involves an alleged hacker currently, Daniel David Rigmaiden, currently facing fraud charges. The government claims Rigmaiden filed millions of dollars in false tax returns.

While Rigmaiden maintains his innocence on all charges, he is also specifically challenging in court the way the FBI hunted him down. Court filings indicate Rigmaiden's wireless mobile internet card was tracked, probably by a Stingray device.

The FBI has responded that all relevant federal law was followed in this case, citing that a judge signed a court order for the Stingray's usage. However, the decision before the courts now is whether the judge erred by signing off on the use of a technology that he neither understood, nor held to the probable cause standard.

Law enforcement authorities have claimed they wish to keep devices like the Stingray out of the public eye, while simultaneously taking the positions that a technology like the stingray is more like a "pen register" than a phone tap.

A pen-register tells who you called and when. We all know what a phone tap is. But a pen-register requires a simple court order, while the tap has to show probable cause.

At the heart of this issue is whether location data requires a higher standard of evidence. And if so, a judge needs to be able to determine exactly what data is being retrieved by law enforcement, and how it is used.

As the case against Mr. Rigmaiden does not involve terrorism or operations on the battlefield, law enforcement attempts to shield the technology from the public could be difficult. We can't have a public debate over privacy intrusions if we don't know how ours might be violated.

A similar case, regarding whether the police can secretly install a GPS on your vehicle without a court warrant, will go before the U.S. Supreme Court in November.

The court may well decide that locational data is protected content absent probable cause.

Alongside that, the court will have to decide the right of the American people to know what tactics are being used against them, even if it hampers law enforcement's ability to catch criminals.

It is hard to decide whether something is unconstitutional if you aren't allowed to know what it is.