reporter: the president repeatedly claimed he didn t know whitaker. i don t know matt whitaker. reporter: but that s not true. if you believe what mr. trump told fox news last month. i never talk about that. but i can tell you, matt whitaker is a great guy. i mean, i know matt whitaker. reporter: a prominent d.c. attorney, george conway, husband of white house counselor, kellyanne conway, argued that whitaker s selection is unconstitutional. it s illegal. and it means that anything mr. whitaker does or tries to do in that position is invalid. the president brushed off conway s concerns. he s just trying to get publicity for himself. why don t you do this? why don t you ask kellyanne that question, all right? she might know him better than me. i really don t know the guy. reporter: but democrats are about to take control in the house and are vowing to protect special counsel robert mueller. the american people spoke on tuesday. they want a check on abuses of power. that
make matt whittaker his acting attorney general, a move that puts a critic of the probe in charge of it. i didn t know matt whittaker. he worked for attorney general sessions. he was very, very highly thought of and still is highly thought of, but this only comes up because anybody that works for me, they do a number on them. reporter: the president repeatedly claimed he didn t know whittaker. i don t know matt whittaker. reporter: but that s not true if you believe what mr. trump told fox news last month. i never talk about that, but i can tell you matt whittaker is a great guy. i mean i know matt whittaker. reporter: prominent d.c. attorney john conway, husband of kellyanne conway, argued in a new york times op-ed that his selection is unconstitutional, it is illegal and it means anything mr. whittaker does or tries to do in that position is invalid. the president brushed off conway s concerns. he is just trying to get publicity for himself. why don t you do this, w