Mr. Monk and the Sleeping Suspect - S2-E7
Deliberate mistake: All the mail bombs are delivered in packages tied with knotted string. The USPO hasn't allowed string-tied packages since the mid-90s (they get caught in automated equipment), but since the knots were crucial to ID-ing the suspect in this episode, that fact had to be ignored.
Mr. Monk and the Man Who Shot Santa - S6-E10
Continuity mistake: At the end, the glass of egg nog Julie and Natalie leave on the floor disappears after they stand up to talk to Monk. (00:40:40)
Mr. Monk and the Red-Headed Stranger - S1-E12
Continuity mistake: In the scene where Willie Nelson is rehearsing, his pigtails change position depending on the shot.
Mr. Monk and the Captain's Marriage - S4-E12
Continuity mistake: In the hospital scene, the items on Gerald's tray change positions several times between takes. (00:27:00)
Mr. Monk and the Game Show - S3-E8
Continuity mistake: Whilst Monk is being introduced to the long standing winner on the show a stagehand is adjusting the microphone on his jacket with both hands. As he says "Are you almost done?" the shot changes and the stagehand is just using his left arm to adjust it. The stagehand then pulls his arm away but the next shot he is adjusting the mic again and using both hands to do it. It keeps changing throughout the rest of the scene.
Mr. Monk and the Actor - S5-E1
Continuity mistake: During the rehearsal, David, playing Monk, rearranges all the items on the coffee table. But each time the camera angle reverses, the items change positions all by themselves, even when he's not touching them.
Mr. Monk Takes His Medicine - S3-E9
Visible crew/equipment: When the armored car is being robbed, the camera pans to the left just before Highsmith is about to kill the driver. During this pan, the reflection of the cameraman is visible on the side of the armored car.
Mr. Monk and the Earthquake - S1-E11
Continuity mistake: Sharona tells her sister that Monk needs the guest room because he "doesn't sleep on couches," but in "Mr. Monk and the Marathon Man," she had to stop him from taking a nap on the victim's couch. (00:15:15)
Mr. Monk and the Very, Very Old Man - S2-E5
Visible crew/equipment: In the scene where Captain Stotlemeyer is putting one of the large snakes back in the glass container, he turns and the base of his wireless microphone is visible when his jacket gets bunched up.
Mr. Monk Takes Manhattan - S3-E1
Continuity mistake: In the scene where the two guys are playing chess, the guy with the black hat knocks over the chess pieces after losing. He then starts scrambling up the pieces and leaving his hands near the chess board. When the shot changes to a wide shot of Monk walking away the guy suddenly has his hands on his head.
Mr. Monk Meets the Godfather - S3-E5
Continuity mistake: In the scene where Monk meets Salvatore Lucarelli (Philip Baker Hall), Lucarelli is cutting up fisheads on a cutting board. Throughout the scene the fish on the table constantly change between shots. One of the notable changes is when Lucarelli is discussing the case he has for monk there is a shot of a fish, and when the shot changes you can now see the fish's head has all of a sudden been chopped off.
Mr. Monk Visits a Farm - S5-E14
Continuity mistake: Natalie carries a large box full of house plants into Monk's kitchen and starts placing them one by one on the counter while he answers the phone. Each time the shot changes, a large red flower switches itself from the left side of one plant to the right side and back again, and sometimes disappears altogether. (00:09:00)
Mr. Monk and Little Monk - S4-E8
Factual error: In the flashback where Monk is explaining how the money was stolen, the principal finds the 5 dollar bill he wrote "good luck" on and holds it up for everyone to see. The bill he holds is a 5 dollar bill which was released in 2000, with the enlarged Lincoln. The flashback takes place in 1972.
Mr. Monk and the Very, Very Old Man - S2-E5
Continuity mistake: In the cemetery scene, Stottlemeyer approaches the grave of the 17 year old open case hit and run victim. The dates on his grave are 1980-1997. But in Dennis Gammill's confession letter in the end, it says he killed the boy in December 1998.
Mr. Monk Goes to the Asylum - S1-E6
Plot hole: Monk and Manny go on the roof through Manny's window to grab a piece of cloth. Due to the possibility of suicide, it is highly unlikely that an asylum would have a window that goes directly to the roof, unlocked.
Mr. Monk Is Underwater - S7-E5
Factual error: Commander Whitaker tries to drown Monk and Natalie by trapping them in the ballast tank of the submarine. The ballast tanks on a submarine are inaccessible from the interior, and wouldn't have dramatic lighting in them either.
Mr. Monk Goes to the Asylum - S1-E6
Factual error: The woman who accuses Monk of stealing her necklace shouldn't have the necklace inside the asylum in the first place. For both safety and insurance reasons, patients in mental facilities aren't permitted to keep any potentially harmful jewelry, including pins, broaches, earrings, belts, beads and necklaces.
Mr. Monk and Little Monk - S4-E8
Factual error: When Monk is talking to Sherry about the painting in the art gallery where the painted woman was going to kill her husband, he says that she has a bruise on her left eye. But the bruise is actually on her right eye. While it is viewable that it is on Monk's left, he would not make that mistake.
Mr. Monk Meets His Dad - S5-E9
Continuity mistake: Jack's big rig has a huge Christmas wreath on the front grill. When the truck loses its brakes, there's an overhead view of it careening down the road, and the wreath has disappeared. It's back in the next shot, though. (00:34:30)
Mr. Monk Goes to the Bank - S6-E12
Continuity mistake: One of the large safety deposit box doors is standing wide open when Monk is curled up in the vault's corner. But when the camera angle changes, the door has closed itself. (00:30:45)
Answer: Notice also that in the opening credits scene when he is touching parking meters her also wipes his hand on his clothes each time he does it.