Sally Shopper drives a 1995 gray Honda Accord. She parks it in a shopping center lot while she shops. Two hours later, Shopper enters a car parked nearby that is almost identical to hers. As she drives away, the owner spots her and demands that a nearby police officer stop her. Just as the officer approaches her, Shopper realizes that she is in someone else’s vehicle. Had she looked at the vehicle more carefully, she would have observed that it had a license tag from a different state and some unique bumper stickers. On complaint of the owner, the officer arrests Shopper and charges her with theft. What is Shopper likely to assert in her defense?