Article II, Section 2, Clause 1:
The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States; he may require the Opinion, in writing, of the principal Officer in each of the executive Departments, upon any Subject relating to the Duties of their respective Offices, and he shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment.
The authority in Article II, § 2, cl. 1 to require the written opinion of the heads of executive departments is the meager residue from a persistent effort in the Federal Convention to impose a council on the President. 1 The idea ultimately failed, partly because of the diversity of ideas concerning the council’s make-up. One member wished it to consist of
members of the two houses, another wished it to comprise two representatives from each of three sections,
with a rotation and duration of office similar to those of the Senate. The proposal with the strongest backing was that it should consist of the heads of departments and the Chief Justice, who should preside when the President was absent. Of this proposal the only part to survive was the above cited provision. The consultative relation here contemplated is an entirely one-sided affair, is to be conducted with each principal officer separately and in writing, and is to relate only to the duties of their respective offices. 2 The Cabinet, as we know it today, that is to say, the Cabinet meeting, was brought about solely on the initiative of the first President, 3 and may be dispensed with on presidential initiative at any time, being totally unknown to the Constitution. Several Presidents have in fact reduced the Cabinet meeting to little more than a ceremony with social trimmings. 4