Several times, the clock in the dining room is unchanged after several minutes have elapsed. On at least three separate occasions the clock reads 9:15.
The detective asks to search Warwick's house, but would not do so without a search warrant.
During the flashback to the bath-tub scene where John is teaching Simone how to play chess, the chessboard is incorrectly oriented (r/h rook starting square should always be white).
At the beginning of the movie when the storekeeper played by George Cheung was speaking Cantonese, the closed captions subtitle for the movie says he was speaking Korean.
The radio alert said John was driving a "1980's maroon Buick plate KRS427". California plate format is #AAA###, so the leading digit is missing. The car is shown having plate # "3CNC443".
Warwick places his police radio down and leaves it in the booth of the parking garage.
The postcard discussed was advised to be sent from the female friend whilst holidaying in Sydney, of post code 2000. However, upon further review of the postcard at the dinner table, it has a circular Post Shop lodgment stamp printed as 'The Glen 3150', which represents a specific Australia Post outlet situated in the suburb Glen Waverley, east of Melbourne. Sydney and Melbourne are about 1 hour 20 minutes flight from each other.
Warwick breaks a plate on the dinner table. After Warwick ties John up at the table with his hands behind his back, John finds one of the plate shards on the table. John takes the shard in his mouth and drops it in his chair. The camera cuts away for a few seconds and then the next time we see John he is using the shard to cut the rope that binds his hands behind his back. John would either have to stand up from the chair or bring his hands in front of him to get the shard from his chair into his hands. Not enough time passed for him to have done either of these things plus Warwick would have noticed.