Goofs

Van Wyck said his system was delicate and susceptible to problems; however, no one mentioned the sound issue. At times, Chopin could be heard outside the sitting room and on the security tapes, both in the computer and security rooms, while at other times, it is missing. Also, the tapes at one point don't pick up the vase breaking or the gun shot, and yet at other times they do.

The tape outline of the body on the ramp does not match the actual position of the body. The tape outline is much farther up the ramp with the head on the upper level of the floor. When the body is shown during the murder, the entire body is on the ramp.

Lieutenant Columbo asks Van Wick to compare the two video recordings. After zooming in at the desk, Columbo reaches into his trench coat pocket and removes Van Wick's art gallery invitation which appears on the desk in one monitor but not the other. The invitation's paper - as removed from his pocket - is noticeably folded vertically with a slight horizontal crease. When Columbo holds the invitation up next to the monitor in the next closeup shot, the invitation is barely creased vertically with no visible horizontal folds. In the following wide shot, the paper invitation is once more noticeably creased both vertically and horizontally.

In the recorded murder footage the guard sees on his monitor, the victim hasn't finished falling to the floor when the front door to the house starts opening; after he races to investigate, the closeup on the monitor shows she is lying on her back on the wheelchair ramp, with her arms outstretched to her sides, when the door again opens through which the guard enters the scene.

The mulch marks under the window (when Van Wych makes them and when Columbo is investigating).

Columbo has the security video (a wide shot of the room) enhanced and is able to read the wording on a card on the mantelpiece, thereby nullifying the suspect's alibi. This would have been impossible. It is stretching technology and image-enhancement way too far to be able to extract a clear image of the card from something that occupies only a few lines of the video image and to manufacture information that was simply not there in the original image.

At minute 18: the security guard sees the murder recording played back to him on his monitor in the guard house, the camera then zooms into his monitor while he is running to the murder scene, seconds later he is seen on his own monitor entering the main house and standing over the murder scene, as the playback is still rolling that wouldn't be possible for the security guard to be appearing on this video that is playing.

The way the killer holds his gun (sideways) and does not aim properly makes it almost impossible for a non-expert to fatally shoot a person with only one shot at other than very close range.

The camera and CCTV cannot record sounds.

Early on it's noted that Mrs. Van Wick wouldn't like Columbo walking throughout her house with his shoes on. Later on Columbo is not only walking around the house with his shoes on, but he lays on Mrs. Van Wick's bed with his shoes on, with no objection from Mrs. Van Wick.

However, Van Wyck was probably making this up and trying to avoid mulch on the floor, showing to Columbo he was definitely right about his theory.

At the beginning of their first meeting, Columbo refuses to shake Van Wick's extended hand, explaining that he has a bad cold. Yet when he leaves 10 minutes later, Van Wick extends his hand again and Columbo agrees to shake it.

However, Columbo is seen shaking hands reluctantly, agreeing to show so degree of trust.

A gunshot (both during the murder and during Columbo's re-enactment) causes the bedroom door to open, but does not cause the folding room-divider doors to close, despite being much closer.

However, Van Wyck never specified the intensity or type of sound needed to open the doors: one can assume that the gun shot sounded like a clap from a distance, hence not opening all the doors in the house (including the front door).

Columbo is in Mrs. Van Wick's bedroom after the gun shot experiment. He asks Mr. Van Wick to turn off the lights. He does so by using the wall switch which turns off the two bed-side lamps. Columbo then reaches over and turns one of the lamps on by hand. This would be impossible since the power was cut off at the wall switch.

However, Van Wyck never specified the mechanism for the wall switches, so it is reasonable to believe that he would have thought of a way to have his wife access the bedside table lamp whether or not the main switch was off.

When Van Wick explains his theory about the flower pot being knocked over, he tells Columbo, "It's just a theory, but, of course, I could be wrong" when, in fact, it's not a theory, because he later shows Columbo a tape of the murder with the flower pot being knocked over.

However, Van Wyck was trying his best to sound inconspicuous.

Columbo sends Mrs. Van Wick to her bedroom so he can perform the experiment of shooting a bullet into the sand. In all the following scenes where the staircase is visible, the platform that she uses to go up the stairs in her wheelchair is at the bottom of the stairs. It should be at the top of the stairs since she would have had to use it to go up to her bedroom.

As the guard watches the murder, a puff of smoke crosses the upper left corner of his monitor when the shot is fired, but it is nowhere near where the killer stood. Clearly, this was a prop gun fired on set to make the sound.

Elisabeth's lower extremities (thighs and legs) are paralyzed (she is paraplegic) and yet she moves her feet with excitation when she is on the bed and has just kissed her husband good night.

When Harold Van Wick leaves for the art gallery, having just shot his mother-in-law dead, she is obviously breathing when he passes her body.

When Columbo and Mr. Van Wick are walking out of the house, after looking inside for mulch footprints, the scene suddenly lights up revealing that a mirror is being positioned out of the camera to shed light on the scene.

When Columbo is conducting his experiment upstairs in Mrs. Van Wick's bedroom, he enters the room with Van Wick, but does not close the door; however, when he turns off the lights, to recreate conditions in the room on the night of the murder, the room becomes dark, even though the door is still open. Then he claps his hands to open the door.

The safe door is in an exterior wall between the window and the main entrance, so the safe would be outside the house.

Baxter is watching the playback tape in his cabin, the camera zooms in on his surveillance monitor and the audience can see Baxter entering the murder scene. He should not have been on the original playback tape.

A gun shot is very loud. It is understandable that Elisabeth almost missed it because she was under the influence of a sedative, but it is impossible for Baxter not to have heard it as his cabin is close enough to the main house for him to arrive on site within seconds after the playback shot.