Columbo alludes to "Candidate for Crime" in both episodes that immediately followed it in the original broadcast schedule. In this episode, Columbo says he's been "working late on the Hayward case," referring to Nelson Hayward, the politician who murders his campaign manager in "Candidate for Crime," the preceding episode. This is an unusual acknowledgment that Columbo handles multiple cases at the same time. Then, in the next episode, "Publish or Perish," Columbo tells killer Riley Greenleaf (Jack Cassidy) that he wants to write a book about his experiences and describes, as an example, the plot of "Candidate for Crime," to which Greenleaf responds, "Lieutenant, very frankly, I don't give a damn about your Senator or your story."
The term "subliminal advertising" referred to and used by the murderer was actually invented by market researcher James Vicary. Vicary claimed that for a movie called "Picnic" playing at a theater in Fort Lee, NJ, he had inserted frames into the film that read "drink Coca-Cola" and "eat popcorn" that were flashed briefly on screen every five seconds during screenings. Though the duration of each flash was too short for anyone to consciously detect, Vicary claimed that this subliminal exposure boosted Coke sales by 18% and popcorn sales by 58%. Advertisers, the FCC, and research psychologists were skeptical, and in an Advertising Age article, Vicary admitted that he had never conducted the subliminal "experiment" - it was concocted as a gimmick to attract customers to his failing marketing business. The concept of subliminal advertising, nonetheless, has continued on as part of our culture.
Even though Arlene Martel is listed in the cast credits as "Tanya Baker", her part was cut completely from the show.
This is the only episode in the series written by Stephen J. Cannell who later created, produced, and wrote The Greatest American Hero (1981) starring Robert Culp (Dr. Bart Kepple) as Bill Maxwell.
Robert Culp's character Dr. Bart Kepple wears a green single breasted blazer at one point. Culp also wore a green blazer in both of his other appearances as the murderer: Investigator Nelson Brimmer in Death Lends a Hand (1971) and Paul Hanlon in The Most Crucial Game (1972).