A DNA Spray Keeps Burglars at Bay

That gadget was  a canister loaded with a harmless solution containing synthetic DNA. If a criminal attempts to burgle a premises fitted with the device, an employee can hit a panic button that alerts police to a crime in progress and simultaneously shoots out a fine mist covering everyone in the room, including the robber. And as each batch of the spray -- which glows blue under ultraviolet light -- has a unique DNA signature, police can connect the robber to the scene of the crime.

Criminally minded readers might now be thinking, "Well, if I robbed a shop, I'd just scrub myself clean when I got home." But as Andrew Knights, managing director of SelectaDNA, explains, the solution isn't so easy to remove. "It will come off within a number of hand washes," he told AOL News. "But if you run through a spray it'll accumulate on the inside of your nostrils and ears and under the fingernails; areas that are difficult to get off." And, he notes, if a criminal doesn't have an ultraviolet light, he won't know where the liquid is lurking.

Hundreds of sprays have been deployed at retailers and banks across the U.K.,and New Zealand; Knights' company, part of Britain's Selectamark security group, is also in talks with U.S. companies.

Knights says the sprays can reduce crime levels, but he admits the unique DNA evidence they offer has yet to be used in a prosecution. 

That's not a sign of failure, though. If a suspect is scanned with a UV light at a police station (almost everyone arrested in the U.K now undergoes this procedure, no matter what crime the person is suspected of) and starts to glow, he says, "They'll generally plead guilty. The criminal knows it's better to make a plea bargain, rather than annoy the police even further by forcing them to go through the DNA testing."

That's exactly what happened when an 18-year-old burglar from the town of Rawtenstall -- some 20 miles east of Preston in northwestern England -- was hauled in for questioning last month. When he walked under a UV light at the station, his arms started to shine, explains Police Constable Phil Buck, a crime-prevention coordinator in the northern English county of Lancashire. The young offender picked up the glow when he broke into a garden center whose roof had been smeared in another crime-fighting substance: SelectaDNA Gel. "He held up his brightly glowing hands and confessed," says Buck, adding that the teen admitted breaking into the gardening store three times.

However, the main aim of the SelectaDNA spray isn't to capture criminals but to scare them away. "Retailers are investing in this technology because they want to move the crime on somewhere else," Knights says. "They are just out to protect their property and staff." That's why every business that uses a SelectaDNA spray also prominently displays a bright yellow sign in their window showing a stick man with a bag of swag being hit by the mist. "Warning," the sign reads. "SelectaDNA spray installed here."