Continuity mistake: During the time Lax is talking to Gail (Herman's mother), the location of the coffee creamer boat relative to the cup/saucer changes a few times, from almost touching, to about a foot away, to about 2" away. Also, sometimes the napkin is under the creamer, other times it is in Gail's hands or by itself, but the napkin returns to being under the creamer. (00:34:09)
Other mistake: Herman said, "I remember, at one point, this girl was running right towards the door, 50 feet away." The flashback view showed a girl maybe 10-15' from the door. (00:21:45)
Continuity mistake: The objects on the desk at Lax's interview with Herman change several times. Sometimes, the tripod is closer to the center of the desk, about a foot away from the file folder, but other times it is closer to where Lax is sitting and one leg is almost touching the folder. The angle of the file folder and distance to the edge of the desk also varies. The Styrofoam cup switches from one side of the desk to the other. (00:17:07 - 00:18:20)
Other mistake: After Julia was hit/killed by the car and a neighbor yelled, "Mrs. Howards? Anybody home? There's been an accident. Julia's been killed", Herman hung up the phone, looked out a window, and saw Julia on a stretcher being loaded into an ambulance and driven away. This was a scene of a deadly accident, which would not entail the ambulance quickly removing the body from the road, especially with no sign of police presence at the scene. (01:09:35)