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: 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."
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.
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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."
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