Character mistake: Columbo took the Beretta off the gun display by inserting a pencil into the barrel of the gun. In a previous episode, he said to NEVER insert a pencil there because it will ruin the groove of the barrel, making it impossible for ballistics to get a match on the bulletin. When using a pencil, Columbo picks up a gun up near the trigger.
Character mistake: When Columbo is in Mr Benedict's house with Mr Benedict, he calculates the cost of Mr Benedict's house at $720,000. A moment later Mr Benedict asks Columbo; "How did you arrive with that figure, $750,000?" (00:43:20)
Character mistake: Twice, Brenner refers to the T-33 aircraft as the Silver Star. The name of the T-33 was the Shooting Star.
Last Salute to the Commodore - S5-E6
Character mistake: After Commodore Otis Swanson is murdered, Columbo goes to the Swanson Shipyard to speak with the Commodore's nephew, Swanny Swanson. Columbo calls him "Mr. Swenson."
Character mistake: Tommy Brown (Johnny Cash) broke his left leg. Throughout the show, he uses his crutch and then his cane on the left side. It should be on the right (opposite) side.
Character mistake: Columbo talks to the cardiologist. The doctor gives him information about his patient, Mr. Williamson. Columbo has no warrant, so the doctor is violating privilege. He wouldn't give that information to Columbo.
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