Factual error: In the series, Columbo does not carry a gun, and in several episodes it is mentioned that he doesn't like guns and/or that he doesn't know very much about them. In the real world, all LAPD officers must carry guns, and they must re-qualify with them at the range six times each year. Also, due to the very nature of their work, they are knowledgeable about numerous types, makes, and models of guns.
Factual error: When Mrs. Williams takes Columbo flying, she does some aerobatics. Neither of them is wearing a seatbelt. No pilot would do that.
Factual error: To make a call, Mr. Bremer enters a seven-digit number on a push-button telephone. The first three keys he punches are 1, 2 and 4. No telephone number in the United States begins with a 1.
Factual error: When Columbo initially latches onto the radio dilemma (which ultimately solves the case) the dial is tuned all the way to the left. He later tells someone that the radio is set to 'Classical 52', but an AM radio starts at 54, meaning 540KHz. There is no 52.
Factual error: Probably an in joke - the wheels of the "airliner" shown landing at LA international airport are those of a B52 bomber. They are very distinctive and look nothing like those on any airliner ever made.
Factual error: In the middle of summer in southern California, water spread thinly on an outdoor ceramic surface would start evaporating immediately and would be gone in about fifteen minutes. The surrounds of the pool would be bone dry by the time Columbo arrived at the scene, nearly an hour after the murderer sprayed the water there.
The Most Dangerous Match - S2-E7
Factual error: Clayton tells Columbo that he had purchased a new transistor for his hearing aid. Hearing aids - even the old types in use in the 1970's - do not have any user-replaceable parts. The only thing that can be replaced is the battery.
Factual error: Near the end of the episode, Jackie Cooper fires a bullet into his hotel room from the balcony using a revolver fitted with a silencer. Hayward also uses a revolver with a silencer to kill Stone. This is a classic Hollywood error, as silencers do not work on revolvers (unless noticeably modified), due to the gap between the barrel and the cylinder. They also don't make gunshots nearly as quiet as shown.
Factual error: Columbo parks across the street from a house where a murder has occurred. The address is given as 1278 Fairfax Drive. Columbo investigates and returns to his car. A house number, 400, is painted on the curb. The house across the street from 1278 would have an odd number, probably 1277 or 1279. It would not be 400.
Factual error: The nurse is smoking a cigarette in the sick bay. By 1975, when the show was recorded, that would not happen.
Factual error: The nurse brings Danziger a sedative and takes his blood pressure. She has her stethoscope in her ears backwards. A qualified nurse would not make that mistake. When she comes in after the murder to do it again, she has the stethoscope in correctly.
Factual error: In common with a number of characters in numerous episodes, Columbo hopelessly contaminates crucial evidence - at the end of the episode he handles the surgical gloves used by the killer with bare hands.
Factual error: Several times, the revolver used to murder the singer is referred to as a "Weatherby" or "British Weatherby." Weatherby is an American manufacturer of rifles and shotguns; they do not make handguns. The revolver used is a Webley, which is of British manufacture.
Factual error: Columbo gives another detective $5 to go to the gun range for him. Technically, that is a bribe and it would cost both Columbo and the other detective their badges.
Factual error: All LAPD officers must re-qualify with their weapons multiple times a year. If indeed Columbo could not "hit the target," as he says to another detective, he would never have made it through the police academy, much less have become a detective and have been promoted to sergeant and eventually to lieutenant.
Factual error: Rakman Habib's driver's license shows that he lives in "Beverly Hills CA 91605." That is the ZIP code for North Hollywood, not Beverly Hills.
Factual error: Columbo asks for a red wine. His host orders a Beaujolais but the butler brings a Bordeaux. Beaujolais is from Burgundy, not Bordeaux. (01:18:40)
Factual error: Columbo is sent to investigate the murder of a man near the Santa Monica Pier. Santa Monica has its own police department. The LAPD has no jurisdiction there.
Factual error: Santini murders Jerome using a revolver with a silencer. Although this is one of the oldest Hollywood tropes, a silencer (properly called a suppressor) does not reduce a gunshot to a whisper; it only cuts the noise to about 110 dB, which is still very loud. In addition, suppressors do not work at all on revolvers, because most of the noise is generated in the gap between the cylinder and the barrel.
Answer: In the show, he was already a Lieutenant. A promotion would put him in the next rank up, which for the L.A.P.D. would be Captain. However, some of a Captain's duties would be overseeing other officers and ensuring they're compliant with policies, regulations, and standards. It would also most likely take him out of the field. This is something Columbo has no desire for as he rarely goes to police HQ's. Nor does he show interest in compliance and standards (for example, not going to his semi-annual evaluation at the firing range). However, he could still be assigned to a higher pay grade based on expertise, which is a form of promotion that does not include rank advancement. This would be going from Lieutenant I to Lieutenant II. I don't believe in the show it's ever started what his pay grade is. Although, in s02e01 (I believe) he mentions making $11K a year. Whether or not this was a true statement on his part, if you could find pay scale information for an LAPD Lieutenant in the 70's, it could give you an idea of his pay grade.
Bishop73