Continuity mistake: When Julie is tutoring Austin, he takes out a beer can, drinks it, crushes it and puts it down on the desk. A couple of shots later when Julie stands up, the beer can has rotated itself slightly without Austin touching it.
Continuity mistake: During the dinner scene at the Van der Kamp's home, Danielle throws her plate against a wall, but when they pan back to her, the plate is still on the dinner table.
Answer: He was investigating the lead not the case.