have to keep the executive in check is to start impeachment proceedings. >> richard, any indication as to why, though, he is asking for or having conversations about his pardon powers? >> well, i think the facts that show why he's doing that, we've seen over the past six months. this is getting worse and worse. the russia investigation and other scandals in the administration. and one way to have that off is to start pardoning the people who otherwise might roll on other people, and eventually endanger the president. but that strategy ought to be met with very, very stiff resistance from congress. the president cannot pardon himself. i wrote an op-ed in "the washington post" yesterday with lawrence tribe discussing that. there is no example anywhere in human history where i've been able to find a king or anyone else pardoning themselves and having it be effective.