Drug-sniffing dogs are right less than half the time, so why do courts still consider them “reliable”?

From techdirt.  For all the high-flying rhetoric over the necessity of drug dogs, they only seem to be good for giving a cop an excuse to search a car.  These dogs will “alert” whenever they receive a subtle command from the officer, so if a cop wants to search a car, he can covertly instruct the dog to pick up on something, even if nothing is there.  The dogs are basically useless in reliably sniffing out anything, and when lives are truly on the line, most people would rather use rats.