also related to tony's "pledging" the fifth:
To "plead the Fifth" is to refuse to answer a question because the response could provide self-incriminating evidence of an illegal act punishable by fines, penalties or forfeiture.
some people here may think whatever you're doing should be illegal but it actually isn't, and isn't punishable by fines or penalties
you just don't want to answer because you've been backing into a corner with no way out besides "I DON'T HAVE TO SAY ANYTHING IF I DON'T WANT TO"
which, on the internet, is basically saying "you have a good point and i can't counter it without making myself look bad"