Electronic Frisking (Terahertz Wave Technology)
- EPIC FOIA - Documents Shed Further Light on Homeland Security Pursuit of Crowd Surveillance: New documents obtained by EPIC under the Freedom of Information Act provide further details on a DHS plan to use an multiples surveillance technologies to search people in public spaces. Previous EPIC FOIA work produced records about a similar DHS program, which the government agency subsequently claimed it had cancelled. However, the new documents obtained by EPIC show that the DHS was still pursuing mobile crowd surveillance as recently as 2011. The technologies include "intelligent video," backscatter x-ray, Millimeter Wave Radar, and Terahertz Wave, and could be deployed at subway platforms, sidewalks, sports arenas, and shopping malls. For more information, see EPIC: EPIC v. DHS (Mobile Body Scanners FOIA Lawsuit) and EPIC: Electronic Frisking. (Aug. 16, 2012)
Terahertz waves sit on the electromagnetic spectrum between microwaves and infrared and can be applied to "see" through solid barriers and identify materials, even in trace amounts. In 2010, a research breakthrough discovered how to use Terahertz technology at a distance of up to 67 feet. The researchers theorized that it would be possible to "identify materials hundreds of feet or even miles away." This research was funded primarily by the Department of Defense and the Department of Homeland Security.
Jingle Liu, the lead physicist on the project, which was run by Rensselaer Polytechnic Institute through Northeastern University, described the technology:
Two lasers at different frequencies aimed at the target together generate a plasma (basically excited, or ionized air). This plasma emits a florescence that is scattered in characteristic ways by the terahertz radiation of the material it hits. The reflection of the florescence is detectable from remote distances.
The Terahertz waves detect a unique "fingerprint" that every substance carries, and can determine exactly what compound or compounds are being carried in packages, boxes, clothing, shoes, or backpacks. The researchers at Rensselaer have already started compiling a "library" of substance fingerprints. The technology does not work through liquid or metal.
The new terahertz technology is currently being tested at a Police shooting range in the Bronx. Police spokesman Paul J. Browne told the New York Times that the technology is currently effective at three to five meters, and that the goal is to get it to work at up to 25 meters away from an individual.
EPIC has previously obtained documents from the Department of Homeland Security ("DHS") about the Department's development of mobile body scanner and crowd surveillance technology. The documents detailed the Department's use of equipment to scan crowds and pedestrians on the street. The documents reference the development of Terahertz technology and refer to it as "cutting edge"
The Fourth Amendment protects individuals from "unreasonable searches and seizures." Terahertz Wave gives law enforcement and government officials the ability to conduct a search of any individual without the individual's knowledge or consent. These "secret searches" are likely to diminish accountability. In addition, the effectiveness of the Terahertz technology is unproven. The technology may be used to pick up even trace amounts of chemicals, meaning that an individual could come under suspicion for something inadvertently encountered on a public surface, and that could be used to subject that individual to further interrogation and searches.
In New York City, where this technology is being developed to assist law enforcement, the police department has already come under scrutiny for the overuse and inappropriate use of the "stop and frisk" program.
- EPIC's FOIA Request to DHS (Apr. 4, 2012)
- DHS' Acknowledgement of EPIC's FOIA Request (Apr. 20, 2012)
- DHS' First Further Response of EPIC's FOIA Request (May 3, 2012)
- DHS' Second Further Response of EPIC's FOIA Request (May 29, 2012)
- DHS' Cover Letter to the First Production of Documents (July 3, 2012)
- DHS' Cover Letter to the Second Production of Documents (July 20, 2012)
DHS' First Production of Documents
- Contract Award HSHQDC-07-C-00016 between DHS and Northeastern University
- Northeastern University Contract Amendment 1 to HSHQDC-07-C-00016
- Northeastern University Contract Amendment 2 to HSHQDC-07-C-00016
- Northeastern University Contract Amendment 3 to HSHQDC-07-C-00016
- Northeastern University Contract Amendment 4 to HSHQDC-07-C-00016
- Northeastern University Contract Amendment 5 to HSHQDC-07-C-00016
- Northeastern University Contract Amendment 6 to HSHQDC-07-C-00016
- Proposal, Wide Area Surveillance and Suicide Bomber Detection Vol. I
- Proposal, Wide Area Surveillance and Suicide Bomber Detection Vol. II
- Proposal, Wide Area Surveillance and Suicide Bomber Detection Vol. III
- Center of Excellence for Explosives Detection, Mitigation and Response, Year One Work Plan
DHS' Second Production of Documents
- Center of Excellence for Explosives Detection, Mitigation and Response, Year Two Work Plan
- Center of Excellence for Explosives Detection, Mitigation and Response, Year Three Progress and Year Four Work Plan
- Center of Excellence for Explosives Detection, Awareness and Localization of Explosives-Related Threats
- Wide Area Surveillance and Suicide Bomber Detection, Phase I PDR Report
- Government Technology: Laser Scanner Could Redefine Airport Security (July 11, 2012)
- Rensselaer: A Revolutionary Breakthrough in Terahertz Remote Sensing (Mar. 22, 2012)
- Time Techland: Police Developing Tech to Virtually Frisk People From 82 Feet Away (Jan. 20, 2012)
- New York Times: New York Police Working on Technology to Detect Concealed Guns (Jan. 17, 2012)
- Wired: Terahertz Detectors Could See Through Your Clothes From a Mile Away (July 12, 2010)
- Technology Review: How Terahertz Waves Tear Apart DNA (Oct. 30, 2009)
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by Ryan Calo, A. Michael Froomkin,