New Issue: Orbital Catastrophe Ahead? Read Now

Radar Makes All Houses Glass

Law enforcement agencies have handheld radar that can “see” through walls via RF signals, raising Fourth Amendment concerns. Larry Greenemeier reports

 

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Doppler radar has been a weather forecaster’s best friend for decades. But more recently law enforcement has found another application. For the past two years the FBI, U.S. Marshals and other agencies have used a handheld Doppler radar machine to conduct surveillance through solid walls. That’s according to USA Today.
 
Called the Range-R, this Doppler device sends radio frequency signals through concrete, wood and other nonmetal building materials and can measure the distance between itself and any moving objects on the other side. The Range-R can detect even subtle motion like breathing, although it can’t yet identify whether the respiration is coming from a person or their pet. Some 200 of the $6,000 devices have been sold.
 
The problem is that law enforcement has used the Range-R sort of “under the radar,” if you will, sometimes employing it without a search warrant. The issue was brought to light in a court case after the device helped U.S. Marshals catch a parole violator at a house in Wichita. Federal appeals court judges were not pleased. 
 
So that’s the current situation: police use of the technology to gain an edge versus concerns about violations of Fourth Amendment protections against unreasonable searches. Stay tuned for the developing legal decisions regarding this particular Doppler effect.
 
—Larry Greenemeier
 
[The above text is a transcript of this podcast.]
 

Subscribe to Support Independent Journalism

Great science journalism requires human expertise, time, effort and creativity. And it costs money. That’s why I and the journalists here at Scientific American hope you’ll join our community.

When you subscribe, you are supporting staff and freelance journalists who are passionate about telling science stories that are true, important and compelling. Our editors and reporters are often experts in their fields, which means they understand the nuances of big discoveries and can untangle the breakthroughs from the hype. With a subscription, you are also supporting rigorous fact-checking to ensure the words we publish are precise and accurate. And you’re supporting original illustrations, graphics and photos that bring you closer to an advanced laboratory, an ice sheet in Antarctica or a space mission in orbit. You’re helping us craft other types of high-quality journalism as well: Our newsletters are carefully written, edited and curated by staffers you have or will come to know and love. Our Science Quickly podcast is based on original reporting, collaboration with editors and scientists and exacting production.

Subscriptions keep this engine running so we can continue to deliver thoughtful, rigorous and independent science journalism to you. In an era of viral misinformation, this work is crucial. If you value what we do, I hope you’ll consider joining us as a subscriber

Thank you,

Jeanna Bryner, Editor in Chief, Scientific American

Subscribe