Do drug sniffing dogs display ‘Clever Hans’ syndrome?

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And we don’t mean that the dogs miss a lot of drugs. They don’t. We mean they result in a lot of innocent people getting searched. About 56 percent of the time, when the dog says, “Search this dude’s cavities and trash his car, that man is as evil as a vacuum cleaner!” the person has done nothing wrong. What’s more, they appear to be racially biased: If the person being sniffed is Latino, the success rate drops to 27 percent.