Death Hits the Jackpot - S11-E1
Continuity mistake: After Lamarr takes off Freddy's undershirt we see the level of the water in the bathtub. Then he drags Freddy over to the tub and breaks his watch. At that time the water level is lower than it was before, even though the water was still running.
Continuity mistake: Columbo wears a tuxedo the entire episode. Hours after his nephew's wedding ceremony, when Columbo's at the police station investigating the bride's abduction, his bow tie is hanging loosely around his neck. Shortly after, as he and the other detectives 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.
Other mistake: When Melissa sends Andy to have a shower we see that there are several sets of clothing in the closet. We see them again in her flashback when she awakes after being kidnapped. They have just arrived in the Bridal (Empire) Suite, and are leaving very early the next morning for their honeymoon. Why would those clothes be in the closet?
A Bird in the Hand... - S11-E3
Continuity mistake: At 8:15 AM, Harold McCain telephones his Aunt Dolores but when she answers the call, the clock on her mantel shows the time as 10:20.
A Bird in the Hand... - S11-E3
Factual error: The license plate on the automobile of Stallions football team owner Fred McBain reads STALLION1, but personalized California license plates can not have more than seven characters ( http://www.vanityplatebystate.com/alphabetical-listing-of-states/california/).
A Bird in the Hand... - S11-E3
Factual error: They are watching a football game on TV with The Stallions playing some other team. The game they are watching is actually a Canadian Football League game between the Edmonton Eskimos and the Saskatchewan Roughriders.
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