James Buchanan actually said...

"By what authority have the committee undertaken to investigate the course of the President in regard to the convention which framed the Lecompton constitution?"

"The resolution of the House, so far as it is accusatory of the President, is confined to an inquiry whether he had used corrupt or improper means to influence the action of Congress or any of its comm..."

"By what authority have they undertaken to pry into our foreign relations for the purpose of assailing him on account of the instructions given by the Secretary of State to our minister in Mexico relat..."

"If this were not the case, then by the purchase of a new territory from a foreign government out of the public Treasury Congress could enlarge their own powers."