Continuity mistake: The broken side mirror that a distraught Stottlemeyer finds dangling from his damaged car wasn't there when Natalie pulled up to the first crime scene. And it disappears again when Natalie runs back to the car and races off to the second crime scene. (00:03:10 - 00:07:15)
Factual error: Monk deflects the policeman's rifle shot and the bullet hits Stottlemeyer's car. But the gun fires just as Monk pushes it aside, and the car is behind them. There's nothing that could deflect the bullet back toward them, so at that angle, there's no way the shot could have struck the car. (00:35:50)
Character mistake: Julie has just passed her driver's test. At the end, she drives up with two teenage friends in the car and offers the stranded Captain Stottlemeyer a ride. Instead of simply accepting, by-the-book cop Stottlemeyer would be lecturing her. California law prohibits new teenage drivers from having other teens in the car. (00:40:15)
Other mistake: When Natalie sits down with Randy eating ice cream, she's says "vanilla fudge, my favorite." But the carton is labeled "chocolate." Plus Randy says he got it out of her freezer, so she would know she bought just regular chocolate ice cream.
Plot hole: There is no other reason for Randy to hand Natalie the walkie-talkie but to fill that plot hole. He is in fact in breach of police rules when he hands his department issued radio to a civilian to answer it while he is on duty. The same goes for Stottlemeyer and the car keys he hands to Monk. Even more so since he knows Monk could not even drive that car to the side in the far fetched scenario that a police car had to be moved while the cop is serving a warrant inside the building the car is parked in front of. (00:01:15)