SWIM was walking past a cop shop 1 evening many years ago, swim was smoking a spliff, one of the vans outside the police station had a dog inside ( locked in) the dog barked like mad when swim and his friends walked past the van, id say from about 20feet away the dog went crazy.
I think if a dog has been trained to sniff out drugs, it will do so automaticly - the way they are trained is that they are rewarded with treats when they succesfully smell what they are after (during training)
In London the cops routinely walk sniffer dogs in train and underground stations ( or at least they used to) the dogs were trained to sit down next to the culprit, i think the same applies to dogs at airports.
Swim had a very very close escape at heathrow 2 years ago, awaiting a flight to Shanghai there was a sniffer dog ( this was sept 11 so swim suspects dog looking for bombs?) anyway, swim had 2 xtc tabs in his backpack, swim was seated next to swims friend who had backpack on floor, (swims was on his back thank goodness) and sniffer dog was sniffing swims friends crotch and his little toiletry bag, swims friend was orderd to open the toiletry bag while swim was in a state of emergency lol Swim got on the plane and was greeted by more dogs in Shanghai airport, needless to say them pills went in swims mouth ready to be swalowed asap. BE FUCKING CAREFUL