Police Are Using Radar Devices To See Inside Homes

In December 2014, in a federal appeals court in Denver, officers made it known they had used a radar device in order to “see through” walls before entering the house and arresting a man wanted for violating his parole. Enter the RANGE-R; a handheld radar device used by U.S. law enforcement agencies to detect movement behind walls.

Deputy U.S. Marshal Josh Moff testified he used a Range-R to detect that someone was inside. At least 50 U.S law enforcement agencies have equipped their officers with the RANGE-R and have been doing so for over two years. Federal contract records show that the Marshals Service began buying the RANGE-R in 2012 and spent at least $180,000 on the devices.

The RANGE-R looks like a fancy stud finder and uses three antennas, two sending signals and one to receiver. When placed on a wall, the device transmits a radar pulse through the wall and reads back the waves returned. No map or diagram of the inside is displayed. Instead, the device detects movement and can tell you how far away an object is. The RANGE-R does not work through metal but, according to their site, it can

penetrate most common building wall, ceiling or floor types including poured concrete, concrete block, brick, wood, stucco glass, adobe, dirt, etc.

Public Left Out

range-rThe agencies have been using these devices with little notice to the courts and without any disclosure to the public as to when the devices are used. A judge in Denver expressed concerns that agents had used the RANGE-R without a search warrant and warned that,

the government’s warrantless use of such a powerful tool to search inside homes poses grave Fourth Amendment questions.

Ideally these devices can be used to keep officers safe when storming buildings or rescuing hostages. However, privacy advocates and judges alike have expressed concerns about how these devices are used and why they have been doing so without public review. The use of this device without a warrant appears to stand in defiance of the 2001 Supreme Court ruling that Constitution generally bars police from using thermal imaging to scan the inside of a building without the use of a warrant. The ruling specifically noted that it also applied to radar-based systems that were in development.

The idea that the government can send signals through the wall of your house to figure out what’s inside is problematic. Technologies that allow the police to look inside of a home are among the intrusive tools that police have.

– Christopher Soghoian, the American Civil Liberties Union’s principal technologist

This is another case of military technology being adopted for civilian policing. RANGE-R is not the only device that peers through walls. Other devices exist that are more advanced and capable of displaying a three-dimensional layout of where people are located inside the building. These devices were designed for the use in Iraq and Afghanistan and are making their way into the hands of state and federal officers.

When U.S. Marshals Services tracked a man, wanted for violating his parole, to a house in Wichita, they used the RANGE-R to detect if someone was in the house. No mention of the devices is made in the report; instead the report only states that officers “developed reasonable suspicion that Denson was in the residence.” The man identified as Steven Denson was arrested and charged with illegally possessing two firearms they found inside the house. Denson’s lawyer sought to have the gun charges removed, in part because the search began with the use of the RANGE-E without a warrant. During which the judge expressed concerns used the device without a warrant and was surprised by the technology.

Privacy advocates want to know how a judge could be surprised by such a powerful surveillance tool when it’s be around for at least two years, and how these devices have been and will be used in the future.

Image from Shutterstock

A UNC Chapel Hill graduate, blockchain enthusiast and analyst. I have a background in programming and IT, strong studies in econ, stats and game theory. I'm interested in online privacy and privacy laws.