The NYPD is testing a new state-of-the art device that will allow officers to detect firearms through the use of natural background radiation emitted by people, Commissioner Ray Kelly said Wednesday.
The vehicle-mounted scanner, provided by the federal Department of Defense, was delivered to the NYPD last week. It uses natural energy known as "terahertz" to reveal a concealed weapon by sensing when an object -- such as a gun -- blocks part of the energy flow, Kelly told a breakfast forum of the nonprofit New York Police Foundation.
Some experts believe it could cut down drastically on the need for police to do stop and frisks.
"We still have a number of trials to run before we can determine how best to deploy this technology. But we're very pleased with the progress we've made over the past year," Kelly said, noting that concealed handguns are the biggest concern for the department.
Kelly actually began mentioning the emerging technology a year ago but the device then was still too large to be mobile or practical, said a law enforcement official. Refinements have made the device small enough to fit into a small van. Similar systems in use at airports and other locations in Europe appear to be even smaller.
During his talk, Kelly displayed photos from a recent test of the system at the police range at Rodman's Neck in the Bronx. The images showed a normal photograph of an off-duty officer juxtaposed with his terahertz image, which depicted a gun-shaped object under his shirt.
Unlike X-ray devices, terahertz detectors don't send energy toward a person being scanned; they are passive, reading the natural radiation coming from a body. The detectors also don't reveal intimate body areas. The detectors are being tested under controlled conditions but officials declined to give details.
At a time when the NYPD is being challenged over its stop and frisk tactics, terahertz devices could be helpful to police if perfected, said retired detective and criminal justice expert Joseph Giacalone.
"This would be a great tool to reduce complaints about stop and frisk by targeting . . . [people] who look like they have the outline of gun," he explained.
Some critics say the NYPD targets blacks and Hispanics in stop and frisks, noting that very few guns are found by such stops. The NYPD has denied such claims.
"It certainly is intriguing to hear about technology that could reduce stop and frisk abuse that is rampant in New York City," said Donna Lieberman, head of the New York Civil Liberties Union. "It raises a lot of questions as well as hopes," she said.
"If refined enough, you only frisk people based on images," said one judge, who didn't want to be named.