"If something is obstructing the flow of that radiation, for example, a weapon, the device will highlight that object," Police Commissioner Ray Kelly said.
Commissioner Ray Kelly in his state of the NYPD address Wednesday said they began testing the new technology days after it arrived last week.
"These images are from a recent test we conducted with an officer carrying a hidden handgun. You get a sense of why we're so hopeful about this tool," Kelly said.
"There's a lot of unknowns here a lot of unanswered questions," said Darius Charney, of the Center for Constitutional Rights.
Critics of the NYPD's best-known gun-fighting tool, Stop and Frisk, are holding their fire until they know more about the weapon scanner.
"Is it going to be a better alternative to aggressive Stop and Frisk or is it going to turn into another civil rights or civil liberties disaster," Charney said.
The concern is that the scanner will be used in a discriminatory way like Stop and Frisk, targeting minority neighborhoods or that the virtual pat-down will detect keys and cell phones as suspicious items.
"I can't say I'm dead set against it, but me and others in the police accountability business are concerned," Charney said.
Commissioner Kelly says they are working with the city's legal staff to ensure proper use of the device which has been under development for a year.
"We are very pleased with the progress that has been made over the past year," Kelly said.
Police in London are already using the weapons scanner. They have worked closely with the NYPD to develop the system for use in the streets of New York. Kelly says more trial runs will be conducted before it is put into full-time use.
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