The Supreme Court has ruled that “police don’t have to extensively document the work of drug-sniffing dogs in the field to be able to use the results of their work in court.” Instead, Justice Elena Kagan wrote for a unanimous court, “courts should apply the same tests to dog sniffs they do when looking at other issues of whether law enforcement officers have probable cause to take action.”
"The question is whether all the facts surrounding a dog's alert, viewed through the lens of common sense, would make a reasonsbly prudent person think that a search would reveal contraband or evidence of a crime," stated Kagan.
The ruling over turned a decision by the Florida State Supreme Court involving Aldo, a drug sniffing police dog who alerted the Liberty County sheriff to the scent of drugs on a truck owned by Clayton Harris during a routine traffic stop. Harris was promptly arrested when officers discovered 200 loose psuedoephredrine pills, a bottle of hydrochloric acid, two containers of antifreeze and a coffee filter full of iodine crystals (all ingredients for making methamphetamine), along with 8,000 matches in the vehicle.
However, when he was again singled out by Aldo two months later during a similar stop, no drugs were found. Harris then asked the courts to throw out evidence that drugs were found stating that the dog’s alert did not give the police probable cause and that “just because a drug dog had been trained and certified to detect narcotics, it was not sufficient to verify his reliability in court.”
As a result the Florida Court said police needed to present training and certification records, as well as field performance records and explanation of those records as well as the dog handler’s own experience and training for the search to be considered valid.