01/24/2013 -

The NYPD is testing a new device it hopes will help officers detect firearms through clothing. Police Commissioner Raymond Kelly hopes future versions of the device can be mounted on police vehicles or worn on officers’ belts.

The T-Ray, as it’s being called, can detect radiation emitted from a person’s body. These radiation waves, called terahertz (THz) radiation, can travel through fabric and packaging, but cannot travel through metal, so images captured by the device could reveal if a person is carrying a knife or gun.

The T-Ray program has been in progress for around four years and is being paid for by the Department of Defense. The NYPD received its first model last week.

Commissioner Kelly described the multimillion dollar device at a speech in New York on Wednesday.

“In an image displayed by Mr. Kelly, the T-Ray scanner highlighted the body of a plainclothes officer in neon green—with a gun clearly visible as a black shape. The image was captured with the officer standing about 30 feet away,” the Wall Street Journal reported. “Another photo showed the machine, tripod-mounted and about the size of an old-style projection television and housed in blue plastic. Officials said in its current form, the machine could be mounted on a truck and deployed to sites identified as prone to gun violence.”

When Kelly first announced the program last year, he said he’d like toincrease the range of the device to 25 meters.

On Wednesday, Kelly added that he'd eventually like to see a version of the machine that officers could carry on their utility belts. 

Civil liberties groups have had mixed responses. On the one hand, there are concerns that the device would let police “search” a person without them knowing. On the other hand, it could help reduce illegal searches.

“If technology like this worked as it was billed, New York City should see its stop-and-frisk rate drop by a half-million people a year [but] the ability to walk down the street free from a virtual police pat-down is a matter of privacy,” New York Civil Liberties Union Executive Director Donna Lieberman said in a statement released last January when Kelly first announced interest in the device.

During the first nine months of 2011, 88 percent of peoplesubjected to stop-and-frisks were completely innocent, according to NYPD data compiled by the NYCLU.

Photo: NYPD