The programmable Accutrac 2000 turntable used in the murder plot was the first example of a brand new and important technology. As an arm scanned the width of the record, an infrared light beam was bounced off the surface and the returning light intensity was read. The turntable was thereby able to measure and store the location and width of each individual track, allowing the user to play only those tracks he wished to hear. This technology would eventually become the method by which vast amounts of digital information could be read using a reflected laser beam, leading to laser discs, CD's, CD-ROM's and ultimately, DVD's.
At the end, Ruth confesses to the murder, in order to avoid having it brought out that she had previously murdered Janie's father. She doesn't want Janie hurt by this knowledge. Yet this woman arranged her brother's murder so that, if the police didn't go for the burglary theory, suspicion would fall on Janie.
As Fowler and Claire walk together through the studio near the beginning, a woman with two bags--one on her left shoulder and one in her right hand--and another woman with a bag on her left shoulder are in the background on their left. Fowler and Claire come to a halt and the two women are twenty feet. The camera cuts to a reverse shot and the women have instantly passed them. The woman with the two bags is now holding them both in her left hand.
When Fowler steals his clothes from the wardrobe department, he puts them into a black garbage bag. However, as he walks out the door, the bag is now light gray.
Fowler and Mark are supposedly watching a live baseball game in LA on TV. Although it's night and they're in LA themselves, the game on the TV is set in broad daylight.
Why is Sgt. Johnston grinning like a loon when Columbo questions the deli owner? Walter Koenig seems to be extremely happy to be working, but it seems kinda inappropriate for the character.
During one of the conversations between Columbo and Fowler, they sit on a hot set, i.e. a area that´s all set-up for filming. But both move things around, which would cause all kinds of continuity errors.
During one scene, Columbo comes running up dockside and watches Bruce the Shark come bursting out of the water, before turning to speak with Sid Daley. You can clearly see a small circle chalked on the back of his raincoat. In the very next scene, the coat is clean, and Columbo has Ward Fowler chalk the circle on his raincoat to demonstrate that the bullet hole in Claire's dress had been made while she was holding her hands in the air.
When Columbo talks to Sid at the Jaws dock, Sid's hair is blown out of place in a few shots but combed perfectly in others.
When Fowler draws the chalk circle on Columbo's back, his left hand is higher. When the camera cuts to a reverse angle, the left hand has instantly dropped several inches.