If you read my blatherings with any regularity, you know how I feel about breathalyzer-type machines. (If you don't, punch this if you feel like catching up.) In short, my position is that the Constitution guarantees you the right to confront your accuser. If courts exclude polygraph evidence on the basis it's both unreliable and cannot be subjected to cross-examination, then they should be excluding all unreliable machine evidence.
Well here's a new twist from Floriduh's own Orlando Sentinal: How many more innocent people were wrongly jailed because of 'wonder dog'? In a nutshell, a dog named Harass II (ya rly) was claimed by his handler, John Preston, to possess an extraordinary ability to track scents, and the dog's responses were admitted as evidence in criminal cases. Eventually one Judge Gilbert Goshorn ordered Harass's vaunted skills tested in the midst of a trial where the dog was connecting the defendants to the crime via scents detected six months after the crime.
The tests exposed that the dog couldn't actually track anything, much less do the amazing feats claimed at that trial. They now know at least three innocent people went to prison for a combined total of over 50 years.
They have no idea how many more were sent up the river on the testimony of a dog.
A dog, ferchrissakes!