Continuity mistake: In the scene where the sheriff and Andy are rolling the girl up in plastic wrap, as they're lifting her out of the van, in one shot the plastic wrap completely covers her head, and in another the top of her head is exposed.
Continuity mistake: In the scene where the Sheriff is wrapping the suicide victim's body, he has a roll of plastic wrap. He is shown with the box, then as he begins to wrap the head, he has just the roll, and in the next shot it is back in the box again. He presumably would have left it out of the box the entire time, since the box would only get in the way of trying to wrap the body. (00:33:00)
Continuity mistake: After the girl shoots herself and two of the guys are arguing by the passenger side door, the front passenger door keeps changing between open and closed between shots. (00:12:15)
Continuity mistake: The blood stain on the rear window of the van is changing its size throughout the movie. One shot/scene, there is almost no blood around the hole, next shot/scene almost whole window is covered with blood. It happens before they have cleaned the van.
Trivia: Near the start of the film, when the first kid has been captured by Leatherface and they're in the basement, the decapitated head on a table beside Leatherface is that of Harry Knowles, film critic and gossip monger of Ain't It Cool News. (00:37:05)
Answer: Erin must have led the police back to the house and then the Hewitt's were taken away so that way evidence could be collected. They must have thought that Leatherface had escaped and was no longer in the house.