muell -- with mueller? how long it can be, what are the questions, what is it about? and giuliani specifically said, what did you say about flynn and why did you fire comey are two questions that would be off the table, which if you were going to ask about obstruction of justice, those are core questions, again, if obstruction of justice is important to mueller. if president trump refuses to sit down, do you think that mueller should subpoena him and take the risk of that subpoena being rejected? >> yes. i say you should test that. look, no person is above the law. we are a nation that triumphs the rule of law. the president is not above the rule of law. and a subpoena was issued to president clinton and they negotiated the terms of it. but the idea that giuliani and trump unilaterally get to keep things off the table that can't be asked, that goes to the very heart of the purpose of a criminal investigation. and i think you said it well, erin, those are very material subjects that must be examined, with the president. >> i want to play for you,