Have you ever had a bad gut feeling about a (generally well-liked) person that ended up being totally justified? If so, what happened?

Quite the contrary. I had a good feeling about the principal of my sons new school, and he was part of the reason why we went for the school.

He didn't last another year there. First he was not seen for months, and now we know that he was convicted for possession of child porn.

Until then I generally had a feeling that I could assess people quite well. Now, that feeling is shattered.