If I were a guessing gal, the arresting officer probably turned the video reorder off while he was speaking over the phone with his commanding officer, not realizing that the audio was still rolling. (You know, the audio during which he lies to his commanding officer about what exactly took place during the traffic stop. The audio where you can hear him flipping through the pages of a book trying to figure out what he can charge her with. Yeah, that audio.) Once they realized a good chunk of video was missing, they decided they had to put something back in to fill the void. A loop of the tow truck it is!