Continuity mistake: When Raymond brings the doctor his milk and pill, the tray with the milk and pill are already on the bedside table.
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.
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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