“That’s unfortunate. It’s also a bit ironic, since one of the concerns that has been raised about these officials is that they will thwart congressional oversight of the executive branch.”

The White House did send a letter, from White House counsel Gregory Craig, explaining its position to Feingold’s panel.

Feingold has become an unlikely ally to Fox News host Glenn Beck and Rep. Darrell Issa (R-Calif.) in the national debate over policy “czars.” These are officials who hold White House positions but are not subject to Senate confirmation.

President George W. Bush also named several czars to his government, but critics of President Barack Obama say the trend has increased under his administration. They argue the proliferation of czars undermines democracy by shifting power from appointed officials and Cabinet members overseen by Congress to White House aides who answer only to the president.

The criticism intensified after Van Jones, Obama’s green-jobs czar, resigned amid conservative outcry over his profanity-laced comments about Republicans.

Sen. Susan Collins (R-Maine), the ranking member of the Homeland Security and Governmental Affairs Committee, in mid-September sent a letter to Obama questioning the number of “czars” within the executive office and expressing concern that the growing number of czars may be undermining Congress’s constitutional oversight responsibilities. The letter was signed by GOP Sens. Lamar Alexander (Tenn.), Kit Bond (Mo.), Mike Crapo (Idaho), Pat Roberts (Kan.) and Bob Bennett (Utah).

Feingold, who is known as a fierce defender of congressional authority, said he didn’t understand why Obama, who campaigned on a promise of providing better transparency and accountability, would decide to avoid answering questions about the growing number of so-called czars in his administration.

“The White House seems to want to fight the attacks against it on a political rather than substantive level,” he said. “I don’t think that’s the right approach. If there are good answers to the questions that have been raised, why not give them instead of attacking the motives or good faith of those who have raised questions?”

Feingold did offer some support for the administration at the beginning of his opening remarks.

He said some critics of the czars are incorrectly labeling a number of Senate-confirmed administration officials White House czars, including Director of National Intelligence Dennis Blair.

Sen. Tom Coburn (R-Okla.) likewise questioned Obama’s decision not to send anyone to the hearing, especially considering his purported commitment to open, transparent government.

“By not having a witness here today … he does himself and his administration a disservice,” Coburn said.

Craig defended Obama’s appointments in a three-page letter, which Feingold entered into the record during the hearing.

In it, Craig argued that none of the positions Obama has created present “any valid concerns about accountability, transparency or congressional oversight.”

“It is true that the president has created a small number of new White House positions to assist him in addressing important matters of great public concern, in critical areas such as the environment and healthcare,” Craig continued.

“Neither the purpose nor the effect of these new positions is to supplant or replace existing federal agencies or departments, but rather to help coordinate their efforts and help devise comprehensive solutions to complex problems.”

Every president has structured his staff in this way, Craig argued, subject to the limits on the number of White House employees established by Congress.

“That is, and always has been, the traditional role of White House staff,” he wrote.

Addressing the constitutional questions, Craig argued that none of the new White House and National Security Council (NSC) positions violates the appointments clause, which requires that “officers of the United States” be nominated by the president “by and with the Advice and Consent of the Senate.”

The Justice Department drafted an opinion during Bush’s administration that a position is a “federal office” if it is “invested by legal authority with a portion of the sovereign powers of the federal government.”

Craig also stressed that none of the White House or NSC positions identified as czars exercise any independent authority or sovereign power.”

“Their one and only role is to advise the president,” he wrote.

Craig said he has asked the general counsels of the various agencies in questions — the departments of State, Treasury, Homeland Security and Labor and the Environmental Protection Agency — to respond directly to Feingold’s concerns in order to clarify the issue.