Love the subject line and yes you're absolutely right the Commodore was very much a sourpuss. But Swawnie was the real creep. Trying to frame sick and alcoholic Mrs Clay to the crime in inhuman. I'm always wondering that if Charles knew about this why didn't he go directly to the police himself? Probably trying to protect his wife? I think that the cops would have nailed the right person anyway but he had to pursue it in the way that he did and of course that got Charles killed too
I guess a lot of people who become amateur detectives in stories end up being the next victim, but Charles Clay is the only one I can think of in a Columbo episode (not counting all those blackmailers). Are there any others?