chundah's right.
u know the lawyers in Angel, Wolfram & Hart? Well, real lawyers don't truck around with demons, but they are just as underhanded. Don't speak with them. If they call you and you pick up the phone, don't tell them anything.
They are quite capable of asking you how you are in a way that sounds like smalltalk -- if you were to say, smalltalk too 'not too bad' -- BANG! that's evidence.
see?
Ask them who they are, and why they are calling you. Then say you've been advised not to speak to them directly, say goodbye and hang up.