Pulled Over

A cop pulls over a car that's been swerving across the lanes of a road.
"Get out of the car, please."
"But I'm not drunk, officer!"
"Listen, it doesn't matter if you're drunk or not. If you don't get out of this car, I'll arrest you anyway."
"Fine," says the man and gets out of the car.
"Okay, now walk this yellow line." The man looks at the line.
"Which one of them do I walk on?"