Continuity mistake: Columbo, who attended a wedding, wears a tuxedo the entire episode. Hours after the ceremony, when he's at the police station investigating the bride's abduction, Columbo's bowtie is untied and hanging loosely around his neck. Shortly after, as he and the others rush to the photography studio, the bow is now properly tied. This situation was too dire to bother redoing it, nor does Columbo ever worry about his appearance.
Caution: Murder Can Be Hazardous to Your Health - S10-E2
Continuity mistake: When Sheba the dog scratches Anders' car her claws are on the glass and the top of the metal part of the door, above the character line. In the photo that Columbo shows, the scratches go much further down the door.
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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