Last week, we discussed the Fourth Circuit’s opinion that the warrantless procurement of cell site location information is a search that violates the Fourth Amendment. This week, we are looking at another method that law enforcement uses to determine cell phone location. Because this technology is relatively new and because many law enforcement officials refuse to discuss exactly how the technology is employed, it has not been established what, if any, due process requirements currently exist. This video explains how the technology works, and this article provides more details.
The new tracking devices are far smaller than devices that have been used in the past. They are actually sufficiently compact that a law enforcement officer could hide one in his pocket with the antenna affixed to his clothing. However, they are passive, meaning they determine the location of the cell phone by receiving the electromagnetic waves that the cell phone emits rather than accessing cell provider routing data or employing older active technologies, like the stingray. Additionally, the passive nature of these tracking devices means they cannot listen in on cell phone calls. Perhaps most importantly, these devices are inexpensive, generally coming in at less than $10,000 each.
The low price has made them accessible to smaller law enforcement agencies at the state and local levels. Records indicate that as many as 25 departments have purchased them. However, those same records indicate that the federal government, specifically the Departments of Justice and Defense, are the largest purchaser of these devices.
According to one of the manufacturers of this technology, law enforcement feels that the passive nature of the devices it does not create “privacy issues.” The ACLU in California disagrees, but no court has opined on the subject as of this writing. Some attorneys believe that a court order may not be required under current federal law. Further, much like the Stingray systems, defense attorneys need to be actively looking for these devices in cases, as it is unlikely the government will share their employment unless specifically asked.