At 1:21-1:22, when Ethan is in Luke's room and sees a picture of Luke and Dwight it is a horizontal picture. Yet when he picks it up, it is a vertical picture. There is only that one horizontal picture on the dresser.
Dwight and his son watch Game 3 of the 2004 World Series together. Earlier, when Ethan looking up "hit and run" on Google, the Google copyright date is 2006.
Johnny Damon is seen batting when Lucas takes a call from his mom. As Dwight (Mark Ruffalo) speaks with her on the phone a crack of the bat is heard. The crowd stands up and watches as Manny Ramirez rounds the bases, presumably after hitting a home run. Johnny Damon is nowhere to be seen.
Half way through the movie, Joaquin Phoenix's, character mentions 'it's been over a month' since his son's death; however, in the next scene, the sergeant overlooking the case mentions it 'has been three weeks' since the accident (to Mark Ruffolo's character).
Just before Ruffalo and son go home to watch the world series he asks his son if they wanted to get a couple of pizza pies which is way too much pizza for two people and when they got home they were eating Chinese food.