Factual error: The murder is solved based on the time the Chinese pulled out of the Olympics. (The episode was from 1975, so it must be the 1976 Olympics.) The Chinese never pulled out of the Olympics or threatened to do so. Taiwan was kicked out of the Olympics by Canada, but Columbo mentions that it was Peking, that is, Communist China.
Factual error: Columbo solves the case based on fingerprints on the shell casings in the gun. No gun, even a prop gun that never fires live rounds, would be put away loaded.
Other mistake: We see Fowler (Shatner) take the gun from the board in the Gun Room. Later, he puts the gun back, but in a different place on the board. Anyone in the Prop Department might notice that the gun had been moved.
Continuity mistake: When Fowler (Shatner) goes into the Wardrobe Department and takes the parka and ski mask, he has a dark green garbage bag. When he leaves that room and goes to the Gun Room, the bag is grey.
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: Devlin proclaims himself to be a staunch Irish Republican but he refers to the Northern Irish city of Derry as "Londonderry." This is the name imposed upon the place by the British and is despised and rejected by Republicans. Devlin would refer to the city as "Derry."
Factual error: In common with many other episodes, Columbo and all the other police officers at the crime scene hopelessly contaminate it - none of them wear gloves or protective clothing. Not one artifact recovered from the scene would be usable as evidence.
Plot hole: Unless Jarvis Goodland has the world's most stupid lawyer, he has nothing to worry about. Columbo searches the greenhouse and uses a metal detector to find the bullet which, supposedly, shows Goodland's gun is the murder weapon. He conducts the search without a warrant and against Goodland's wishes - he asks him several times to desist with the search and leave. Any evidence discovered or collected during the search is inadmissible in court.
Factual error: An important plot point is that diamonds do not burn and can be recovered from the ashes of a cremated body. This is completely wrong - diamonds would combust freely at cremation temperatures, and since they are pure carbon they don't even leave any residue.
Character mistake: Art expert Dale Kingston describes Goya as 'the penultimate artist'. "Penultimate" has nothing to do with greatness or artistry, it means second to last, and nowhere during his speech does he indicate that Goya is 'second to last' in anything to do with the discussion. In the context he uses it the word is completely meaningless.
Plot hole: Columbo is in the Pauley's hotel room trying to figure out how the bottle landed upright next to his body after he was shot. Devlin - the murderer - turns up unannounced and uninvited. How did Devlin explain that he knew where the victim was staying when he was murdered? Media reports might have mentioned the name of the hotel but there is no way they would have included the room number.
Factual error: In common with many other episodes neither Columbo, the attending police officers or forensic investigators wear gloves or other sterile gear while examining the murder victim's body or the crime scene. Columbo hands out bananas to other people on the scene which they happily eat. The senior crime scene forensics officer, Kingsley, hands out coffee and doughnuts! Eating and drinking are absolutely forbidden on a sterile crime scene, which has been hopelessly contaminated with fingerprints anyway.
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.
Character mistake: Columbo explains to Hayward (the killer) how the accepted version of events is impossible, because when he was shot Harry Stone was standing in a dark garage and the killer could not have angled the headlights of his car in such a way that he was made visible (in order to be shot). But neither he nor Hayward even consider the possibility that the killer could have been carrying a torch, which would not only have illuminated the scene, it would have dazzled the victim and hidden the shooter.
Factual error: Despite the fact that other officers are doing so, Columbo does not wear gloves while examining the crime scene. He also eats and drinks in the room - both absolutely forbidden - leaving eggshells scattered about the place. The crime scene is now totally compromised and nothing found can be used as evidence.
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: 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.
Character mistake: Columbo discusses the murder of Jennifer Welles with Alex Benedict - who killed her - and he reveals that the odometer reading of Benedict's car showed an extra nine miles despite the fact that it was supposedly immobilised in a garage on the night of the murder. Benedict challenges Columbo, saying that he assumes that he has established the distance between the garage and Jennifer's apartment. "Yes, sir." says Columbo. "Exactly nine miles." Since the murderer would have had to have driven to and from the garage to the scene of the murder - the car was back in the garage when the police searched it the next day - shouldn't he have said "Exactly four and a half miles."?
Factual error: There is not a cat in hell's chance that Columbo would be allowed to take charge of the dogs Laurel and Hardy unsupervised and unaccompanied, regardless of his faith in their "deprogramming." These dogs are known to have killed a human being! If they had to be moved, they would be muzzled, attached to a very sturdy chain leash, and each would be led by an armed police officer who would have orders to shoot them if they showed any signs of hostility.
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.
Answer: "Apparent" drowning answers your question - things are not always as they seem. Drowning could be accidental, but it could also be a murder in disguise. Moreover, the actual cause of death has not yet been determined - accident, suicide, murder, or natural cause (e.g, heart attack while swimming). Columbo would be there to investigate if anything looks unusual for it to be a mere drowning or if there is evidence or suspicion of something else.
KeyZOid
This was just on TMZ.com's "Aaron Carter Dead at 34" (11/05/2022): "Law enforcement sources tell TMZ... homicide detectives have been dispatched to the scene but we have no information or evidence of foul play. It's standard operating procedure for homicide detectives to investigate such [drowning] death scenes."
KeyZOid