Article I, Section 8 says Congress shall have the power "To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof."
The Constitution specifies the method in which laws are to be passed in article I, section 7. Were such oversight laws passed by Congress and signed by a President (or was a veto override made)? Or was this another case where an activist Supreme Court made the decision that 'in order to do things right, it should be this way, and instead of making the government follow the Constitution and pass such laws (which they may not be able to do) we shall just decree it', such as in McGrain v. Daugherty (1927)?
Oversight is an implied rather than an enumerated power under the U.S. Constitution. The government's charter does not explicitly grant Congress the authority to conduct inquiries or investigations of the executive, to have access to records or materials held by the executive, or to issue subpoenas for documents or testimony from the executive. CONGRESSIONAL OVERSIGHT
There was little discussion of the power to oversee, review, or investigate executive activity at the Constitutional Convention of 1787 or later in the Federalist Papers, which argued in favor of ratification of the Constitution. The lack of debate was because oversight and its attendant authority were seen as an inherent power of representative assemblies which enacted public law. Historian Arthur M. Schlesinger, Jr., has noted that ``no provision in the American Constitution gave Congress express authority to conduct investigations and compel testimony.''15 He added, ``but it was not considered necessary to make an explicit grant of such authority. The power to make laws implied the power to see whether they were faithfully executed. The right to secure needed information had long been deemed by both the British Parliament and the colonial assemblies as a necessary and appropriate attribute of the people to legislate.''16
Oversight also derives from the many and varied express powers of the Congress in the Constitution. It is implied in the legislature's authority, among other powers and duties, to appropriate funds, enact laws, raise and support armies, provide for a Navy, declare war, and impeach and remove from office the President, Vice President, and other civil officers.17 Congress could not reasonably or responsibly exercise these powers without knowing what the executive was doing; how programs were being administered, by whom, and at what cost; and whether officials were obeying the law and complying with legislative intent.
The Supreme Court made legitimate the oversight powers of Congress, subject to constitutional safeguards for civil liberties, on several occasions. In 1927, for instance, the High Court found that in investigating the administration of the Justice Department, Congress was considering a subject ``on which legislation could be had or would be materially aided by the information which the investigation was calculated to elicit.''18
FOOTNOTES15 In Arthur M. Schlesinger, Jr. and Roger Burns, editors, Congress Investigates: A Documented History, 1792-1974, New York, Chelsea House, 1975. v. 1, p. xix.
16 Ibid. See also Telford Taylor, Grand Inquest: The Story of Congressional Investigations, New York, Simon and Schuster, 1955. pp. 1-16.
17 U.S. Constitution, Article I, Section 8 and Article II, Sections 2 and 4.
18 McGrain v. Daugherty, 273 U.S. 135, 177 (1927). See also Watkins v. United States, 354 U.S. 178, 187 (1957) and Barenblatt v. United States, 360 U.S. 109, 111 (1959).
Note also (from reply #156 above): "The first congressional oversight investigation took place in 1792, an inquiry into the conduct of the government in the wars against the Indians, and they have been taking place ever since."
Bear with my stream of consciousness here. You have posed a very good question. I really don't know the answer to it. It seems that for a recommendation or request for information to come out of committee, a law will have to have been passed (under the Constitution) that divests the authority to that committee. If each request for information was put up for a general vote, the requirements for passing it would be the same as an conviction for impeachment, and that doesn't seem probable or efficient. Any president under investigation could stonewall all day long (come to think of it, as Clinton did) by denying information relating to the investigation.
We do know that the people have the right to access documentation relating to the governing of the nation, which is protected by the Freedom of Information Act of 1974. That act does not apply, however, to those, such as the Chief Counsel or Chief of Staff, whose sole function is to advise and assist the president. The AG and the Justice Department prosecutors, however, have more than simply an advisory role.
Now let's speak in more general terms as to the checks Congress has over the executive branch.
"Nothing could be more irrational than to give the people power and to withhold from them information, without which power is abused. A people who mean to be their own governors must arm themselves with the power which knowledge gives. A popular government without popular information or the means of acquiring it is but a prologue to a farce or a tragedy, or perhaps both."
--James Madison
I'm reminded of a situation Alexander Hamilton got himself into when our nation was still in its infancy. While he was Secretary of Treasury, he had an affair with the wife of a criminal. He paid him something like $10,000 in "reparations" for it, out of money he borrowed from a friend.
When the anti-federalists got wind of the money being paid out by Hamilton, they accused him of using taxpayer money for it. Hamilton invited those congressmen into his private chambers and confessed the entire affair, but assured them that he did not use taxpayer money. The men in the room, Hamilton's political enemies as it so happens, promised they would not embarrass him with the affair. Naturally, they just held onto that card until it was most useful to them.
When word of the affair was leaked, national suspicion fell on Hamilton... He didn't have to, but he felt compelled to write a brief treatise to be published in the newspaper, confessing his affair to the nation, and demonstrating that he didn't use taxpayer money to bribe the woman's husband.
That's the short version... but the reason I included it here is because it is one example that demonstrates the accountability and transparency the founders expected out of the elected officials. I would think at least Madison and Hamilton would be opposed to the seemingly whimsical and uninhibited use of "executive privilege," when it comes to investigating possible crimes of current or former administrations.
In such cases where information gathering relating to public officials must take place, however, my first reaction is not to question the legitimacy of the request, but the legitimacy of the denial.