Melville Fuller

“ The validity of a statute is not drawn in question every time rights claimed under such statute are controverted, nor is the validity of an authority every time an act done by such authority is disputed. ”

“ Chief, Justice TANEY that the duties to be performe b y the head of an executive department of the government, whether imposed by act of congress or by resolution, are not, in general, mere ministerial duties; that departmental duties are executive in their nature ”