That reminds me of the time I was taking a polygraph test and the tester asked me if I had ever done anything I didn’t want anyone to know about...after I responded with a yes, he got really upset when I wouldn’t tell him what it was.
Any adult who hasn’t done something he doesn’t want the world to know about hasn’t really lived. For some reason I’m thinking about an old girlfriend who I still think of fondly. Wow, I’m glad there is no video.
I don't approve of questions like that for a lie detector. Every body has at least one thing, and it'll spike the values just remembering it. It's a question designed to make you fail, no matter what. For that matter, I don't approve of "lie detectors."