Opening a locked vehicle to remove property that does not belong to you is legal. The outdated parking pass would be considered property of the apartment complex, not yours. The law firm I am currently doing some intern work for represents many towing companies and while being supervised by a police officer, the tow truck drivers are allowed to open vehicles to remove property that does not belong to the registered owner. The police or driver are not allowed to search the vehicle though. The tow truck driver may also open the vehicle to release the parking brake and shift the transmission if necessary to move the vehicle without causing damage. As I was just advised by a senior attorney and former judge, unless something besides the parking pass was taken, there were no laws broken.