A (bit.ly) linked article at http://www.cleveland.com/metro/index.ssf/2013/06/fake_drug_c... quotes an assistant prosecutor: "Vitantonio said that if Peters had not given police permission to search, they would have had to let him go."

That said, it is possible that a trained canine might have alerted from outside the car, generating enough probable cause for a legal search inside of the car without consent of the driver.

This is an area that has seen a lot of litigation in the last 30 years or so, for details google "probable cause" "canine" "Place" "Jardines" "Harris" and "Caballes".