The chalk on the tread of the tire proves you didn't just get there, though. If you did, then it would not have been possible for the parking enforcement office

The chalk on the tread of the tire proves you didn't just get there, though. If you did, then it would not have been possible for the parking enforcement officer to have chalked it an hour ago. But if it's on the pavement, it's not crazy to imagine the marks were for a previous car, and that you parked in the same spot. Even the officer would be unsure of it.