The Dutch police conducted a pilot many years ago to see if dogs could detect gun shot residue on hands in a reliable manner. This was when doing forensic GSR examination took a long time, stubbing hands and then using microscopy. We ended up with severe logistic problems in training the dogs since the only place we were allowed to shoot was in one or two indoor firing ranges and only gun-carrying personnel was allowed to shoot. The dogs quickly learned to respond to odours linked to these firing ranges. We could not shoot outdoors – I’m sure you guys can! Happy to tell you more if you think it would be useful – just contact me.
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