done legally. they say they have that power or think that power should exist but didn't indict a president as you know. doj guidelines and a debate over what they mean. they're not law. the man who wrote the ones for the special counsel said this. >> regulations say mueller you're bound by doj policy but can seek exceptions. that's what i would expect he would do. >> that's why all of the backstory in the legal history matters tonight. we don't know what mueller is going to do. but if, according to the man who wrote his rules he uncovered the kind of crime that was so significant that he needed or thought there was a public interest to indict a sitting president, he would have to ask for an exception. he would have to do that. he would have to do that request by submitting it to the new current attorney general. they ultimately ordered nixon to turn over those very damning watergate tapes. they said the president didn't