Dog detectives get trained to sniff out knives
BBCAn American university and dog trainers in Plymouth are researching how dogs could help police find knives used to commit crime.
The dogs involved in the research project do not detect the knives themselves but a chemical compound created by the blades when they make contact with human skin.
The smell of a knife in contact with human skin has been synthesised into a liquid form at Texas Tech University and the dog trainers use that to train the dogs, said trainer Brian Mence.
A spokesperson for Devon and Cornwall Police said although they are not yet using dogs to detect knives, "we are aware of the training and capabilities of using search dogs to tackle knife crime".
The process of getting the dogs to recognise the smell is similar to other working sniffer dogs.
Dog trainer Brian Mence explained it is a bit like handling coins or drinking out of a metal can.
Although dogs are not currently being used by police forces in the UK for finding knives, lead trainer Andy Lightfoot believes there are several advantages to using dogs for this purpose.
"They're mobile, they're flexible, we can jump from one access point to the next, and they are non-invasive making the whole search process a lot quicker," he said.
Unlike a metal-detecting arch, which will alert to any metal item, the dogs only react when there is a blade, he added.
"It's building the association with the odour for a reward - in most cases that is giving them their favourite toy.
"Once they have that, they can search bags, coats, and then we can build up to searching people."
A Home Office spokesperson said: "We remain steadfast in our mission to halve knife crime over a decade.
"That's why we are bringing in new laws to stop knives from being sold illegally online, have banned zombie style knives and machetes, and are putting more neighbourhood police officers on the streets to make our communities safer while driving the development of innovative knife detection technologies."
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