Just because republicans did it, doesn't mean it was constitutional...prehaps they got away with it?? Or does it state that Congress is allowed oversight into any matters pertaining to the hiring/firing of staff by the elective branch??
Congress's roll in oversite ends at comfirmation, they get absolutely no say beyond that point.
Congress does have oversight of the DoJ and all cabinet departments.
They should testify under oath, w/ a transcript in private.
Further heres a piece on Congressional Oversight from 2001
http://www.senate.gov/artandhistory/history/resources/pdf/CRS.Oversight.pdf
Underlying the legislature's ability to oversee the executive are democratic principles as well as practical purposes. John Stuart Mill, the British Utilitarian philosopher, insisted that oversight was the key feature of a meaningful representative body: “The proper office of a representative assembly is to watch and control the government.”1 As a young scholar and future President, Woodrow Wilson—in his 1885 treatise, Congressional Government—equated oversight with lawmaking, which was usually seen as the supreme function of a legislature. He wrote, “Quite as important as legislation is vigilant oversight of administration.”2
The philosophical underpinning for oversight is the Constitution’s system of checks and balances among the legislature, executive, and judiciary. James Madison, known as the “Father of the Constitution,” described the system in Federalist No. 51 as establishing “subordinate distributions of power, where the constant aim is to divide and arrange the several offices in such a manner that each may be a check on the other.”
In sum, oversight is a way for Congress to check on, and check, the executive.
The U.S. Constitution
Although the Constitution grants no formal, express authority to oversee or investigate the executive or program administration, oversight is implied in Congress’s impressive array of enumerated powers.3 The legislature is authorized to appropriate funds; raise and support armies; provide for and maintain a navy; declare war; provide for organizing and calling forth the national guard; regulate interstate and foreign commerce; establish post offices and post roads; advise and consent on treaties and presidential nominations (Senate); and impeach (House) and try (Senate) the President, Vice President, and civil officers for treason, bribery, or other high crimes and misdemeanors.
Reinforcing these powers is Congress’s broad authority “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 authority to oversee derives from these constitutional powers. Congress could not carry them out reasonably or responsibly without knowing what the executive is doing; how programs are being administered, by whom, and at what cost; and whether officials are obeying the law and complying with legislative intent. The Supreme Court has legitimated Congress’s investigative power, subject to constitutional safeguards for civil liberties. In 1927, the Court found that, in investigating the administration of the Department of Justice, 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.”4
There is a long history behind executive reports to Congress. Indeed, one of the first laws of the First Congress—the 1789 Act to establish the Treasury Department (1 Stat. 66)—called upon the Secretary and the Treasurer to report directly to Congress on public expenditures and all accounts. The Secretary was also required “to make report, and give information to either branch of the legislature ... respecting all matters referred to him by the Senate or House of Representatives, or which shall appertain to his office.”
Party line and blogger quoting may now continue