In the scene where Whitlock explains his GPS-equipped device to his soon-to-be ex-wife, the time in the PocketPC's upper right corner is displayed as 9.21. The camera changes, and when it comes back just a moment later the time is shown as 9.39.
Upon arriving in Cabot's hotel room the dialog from Legally Blonde can clearly be heard. After fighting with Cabot, dangling over the side of the balcony, and struggling back into the room (all of which took several minutes) the dialog has clearly only progressed for a few seconds, not minutes.
As Chae is driving Matt back to the police station after raiding Cabot's house, he throws a cigarette out of the car. However, as the camera pulls back and the car continues moving, there's no sign of the cigarette on the ground.
The mirror in the center of windshield is missing from the interior of the car as Denzel drives up to the hotel. However, when the camera cuts to show the car pulling up to the curb, the mirror has suddenly reappeared.
Chief Withlock has apparantly been chief of police for quite a long time and Dr. Frieland has been a doctor for 10 years in the only hospital in town. But when they bump into each other they don't seem to know each other, despite the fact that chief Whitlock's picture has been on the front page of the paper. It has to be that Dr. Frieland does not read newspapers or he does not live in Banyan Keys.
When Matt is sneaking around Ann and Chris' house, attempting to deliver her the money, and prior to the fire, the motion light of the neighbor's house turns on to reveal his presence to the neighbor. Matt, who was engaged in an adulterous affair with Ann, would most likely be aware of this light.