Nope. The dog's response then becomes probable cause to search the car. If no contraband is found during the search, you'll still walk.
Of course, they can always plant something during the search, but somehow I suspect most of the claims that this happened are from people with little credibility on the subject.
For that matter, the cops (or anybody else) can break into your car and plant drugs that you would have no idea are there. The K9 finds them and you go bye-bye. Your only defense at that point is your reputation.
If the "suspect" insists on it, wouldn't they still be required by law to get a warrant?
“Of course, they can always plant something during the search, but somehow I suspect most of the claims that this happened are from people with little credibility on the subject.”
Familiar with the Ramparts scandal in LA?