immunity. it stems from the notion that congress can't force the president of the united states to come and testify. he also can't then force his senior adviser to come testify. it's taken by presidents and department of justices in both parties but it's untested. we don't know what the supreme court will do with that. >> i think there's the belief out there that executive privilege means that congress can't force anyone who works in the white house to testify, whether it's don mcgahn or kupperman, national foreign adviser. is that wrong? >> at first they're trying to assert something even broader than executive privilege which is absolute immunity. i have to disagree with ross a little bit. there is some precedent. in 2008 district court judge soundly rejected the idea of there being this absolute immunity, specifically citing the nixon case, saying that