of course grime cued the dogs..it's standard practice
The following extract is taken from the comprehensive overview of Forensics by Dr Zakaria Erzinclioglu (Forensics - True Crime Scene Investigations: Carlton/ Sevenoaks, 2004) and illustrates perfectly clearly how those with a professional concern for the appropriate deployment of dogs in law enforcement, have a rather clearer understanding of experimental verification and how to garner evidence than do their amateur critics. And in that category I do not hesitate to include members of the Judiciary.
"Cloths are handed to each of the people involved in the experiment; they handle them and then place them in special jars, with each cloth in a separate jar. The jars are placed in a row in the experiment room and the dog and handler come in. The dog sniffs each jar in turn and then identifies correctly the jar with the right cloth... the jars are moved around in the absence of the dog, who returns with his handler and correctly identifies the cloth.
"These results are very impressive, but, to my mind, the results of the next experiment are the most impressive of all. The jar with the 'right' cloth is removed completely, leaving all the other jars, plus another to keep the number constant. What will the dog do now?
"As with the other experiments, the dog is led by its handler into the room. The dog sniffs each jar in turn. It is puzzled. It starts again, sniffing each jar diligently. It stops and looks up at its handler and then looks back at the jars, It then starts to whine to its owner and walks away from the jar; no doubt it feels it has failed in its task.
"But it has not; it has succeeded brilliantly, for the dog has not chosen a second best, a nearest odour to the one it was seeking. The smell was either present in one of the jars or it was not. It is as simple as that. The dog would not identify a false jar even to please its handler; it would rather fail than do that."
This author goes on to say, "I believe that the use of dog evidence in British courts would be a great step forward in the fight against crime." He concludes the chapter thus:
"Attempts have been made to produce a machine - an electronic nose - that can do what a dog does. These devices have been very successful in determining whether a food product, such as wine or cheese, is fresh and in a fit condition to be consumed. However, their application to criminal investigation has not yet been demonstrated. A dog is still the more reliable tool."
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