agreement, for flynn's lawyers and the white house's lawyers? >> a very common practice. when people are the subject of an investigation it's normal for people who know that the subject with other people, that there's a group of them to have a common defense agreement. that protects the attorney/client privilege and let's them form a strategy together. >> how common to break that agreement? >> also not uncommon. as a rule, what we see are people will form these types of agreements and if someone wants to have a conversation with the government and it could be as you mentioned because they're cooperating. could also mean they're talking about plea deal, at that moment lawyers are ethically bound to break out of that agreement and not be a part of those strategic confidential agreements. >> and all sorts of angles. not reveals information with foreign governments and a plan to smuggle out, to kidnap somebody in america and deliver