The situation being when you are accused of something, and provide a logical reason why you wouldn't (not couldn't) do such a thing, and such an explanation only makes you sound more guilty.
For example, if your boss has recently been murdered, and your coworkers know you didn't like him, and someone accuses you of killing him, and you say something like "Why would I do that? He just gave me a raise!" (This isn't the best example, I'm sure there are reasons that would seem more manufactured.)
I think this is one of the situations that the 5th amendment tries to protect against in court. It seems to be a subtle form of double bind, since not defending yourself makes you seem guilty, as does defending yourself.
Is there any term for this situation in English?