I sold a car several months ago. A couple of days ago I received a notice from the DMV, telling me that I must pay a fine of $148 for non-payment at several automated toll booths on one of our state highways. They say they have photos of my license plate, and ownership records list me as the owner.
These infractions took place after I sold the car, and I know nothing about them. The person I sold the car to promised to re-title and register the car immediately after the purchase, but apparently did not do it. I can prove that I sold the car prior to the infractions, and that I was at work on the dates and time at which they occurred.
Can someone explain what my liability is, if any, and how I might defend myself against the charge?

