The New York Police Department is using super secret X-ray vans and it is something the authorities want to keep tight-lipped about. The vehicles, known as Z Backscatter Vans, patrol the city streets and, while the NYPD is not disclosing what it is doing with them, it is understood they have the ability to see into the contents of cars or even inside homes as a counter-terrorism measure.

The X-ray vans have the technology to penetrate through the body of a vehicle as it drives past to see whether there are weapons, explosives or drugs inside - something often used by immigration patrols. The same could potentially go for the walls of buildings and houses or even see what you are keeping under your coat. The worry from members of the public is whether the X-ray vans are being used on people as a means to search for concealed weapons and if so, what are the health and privacy implications.

NYPD x-ray Z Backscatter Van
Just an ordinary van? Nope. This one can see inside your car to know what you're hiding

The New York Civil Liberties Union has been pushing Police Commissioner Bill Bratton to shed some light on the X-ray vans by filing a case that the NYPD should release records about them, but he remains defiant to give anything away.

"Those issues I'd prefer not to divulge to the public at this time," Bratton said in a story by the New York Post. "I will not talk about anything at all about this – if falls into the range of security and counter-terrorism activity that we engage in."

NYPD x-ray Z Backscatter Van
The NYPD could know what is inside vehicles around the city, but are they looking into homes?

The NYCLU has requested to file an amicus brief on the grounds of the public not knowing what they're being used for or if they could be harmful to human health.

Are NYPD's x-ray vans harmful to health?

"People should be informed if military grade X-ray vans are damaging their health with radiation or peering inside their homes or cars. New Yorkers have a right to protect their wealth, welfare and privacy," said NYCLU executive director Donna Lieberman.

Bratton, however, gave a stout response: "They're not used to scan people for weapons. The devices we have, the vehicles if you will, are all used lawfully and if they ACLU and others don't think that's the case, we'll see them in court – where they'll lose!"

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