The Democratic-led Congress appears intent on using its oversight powers to investigate the Bush administration until the day the latter packs up and walks out of the White House.

Oversight hearings and reports have been as common as lobbyists on Capitol Hill since the Democrats swept the 2006 elections. In July alone, hearings covered a range of subjects including allegations of faulty wiring installed by US contractors in Iraq, possibly misleading testimony from Environment Protection Agency (EPA) Administrator Stephen Johnson, and charges that politics guided hiring of career workers in the Justice Department.

White House officials consider the scrutiny a burden and a waste of legislative time.

"When you have divided party government, you have more vigorous oversight," says James Thurber, director of the Center for Congressional and Presidential Studies at American University.

With Election Day only three months away there's little time left for the lame-duck Congress to push for substantive changes in response to the lame-duck Bush administration's alleged misdeeds.

Take the issue of executive privilege. Democratic congressional leaders investigating the mass firing of US attorneys in 2006 have long demanded that former political aide Karl Rove and other Bush officials testify before Congress. But they've refused to appear, citing executive privilege – the legal doctrine that holds a president is entitled to keep conversations with staff private, in order to promote candor.

On July 30, a federal judge rejected the White House's claim that executive aides have immunity from congressional oversight. But the legal wrangling on this issue is likely to stretch on well past election day. It remains to be seen whether the next Congress will care to pursue this issue once Bush himself is out of office.

On executive privilege "Congress has not been that successful," says Mr. Thurber.

What oversight can achieve

The purpose of congressional oversight is not necessarily legal change, however. This counterpart of Congress's legislative powers is also meant to reveal problems and ensure the exercise of constitutional responsibility on the part of the executive branch.

"To assess the oversight of one year can take several years," says David Rohde, a political scientist at Duke University.

Rep. Henry Waxman (D) of California, chairman of the House Committee on Oversight and Government Reform, has long championed congressional oversight authority as an often overlooked, vital function.

Done right, it can shape national policy just by producing public information, said Mr. Waxman at a 2006 symposium on the subject.

In 1994, Congress held extensive hearings into the practices of the tobacco industry. These did not lead to any enacted bill – then, or in subsequent years.

But the hearings forced tobacco executives to talk on the record and under oath, and to release thousands of pages of internal tobacco industry documents. State attorneys general used this information to bring the lawsuits against the industry which eventually led to restrictions on tobacco advertising and a monetary settlement worth over $200 billion.

"It would be wrong to ascribe these accomplishments to the congressional hearings ... but without question, those hearings [in 1994] had a galvanizing effect," said Waxman.

Now Waxman is one of the primary oversight irritants to the Bush administration. He's probed everything from reconstruction in Iraq to the firings of US attorneys to alleged politicization at the General Services Administration.

For officials, a waste of time

"One thing that is clear is that there is a heckuva lot more oversight than there was [before 2006]," says David Rohde. "But a degree of it is for show."

That's the main complaint of the Bush administration – as it was for the Clinton administration.

The White House calculates that it has had to respond to more than 300 congressional investigations or inquiries. As of last December, officials estimated they'd produced more than 1 million pages of documents in response to these probes.

Officials grumble that voters are far more concerned about the price of gas than whether Karl Rove will be forced to respond to the latest congressional subpoena.

It's true that polls show congressional approval ratings at record lows. A Gallup survey in early July found that only 14 percent of respondents approved of the job Congress is doing – half of President Bush's own record-low job approval rating of 28 percent.

Tension over oversight is as much institutional as partisan, says Thurber.

Every White House resists inquiries from Congress, particularly when it's controlled by the opposition party. The Clinton administration too complained it had produced more than 2 million pages of documents for congressional inspection from 1996 to 1998. White House staff spent over 55,000 hours responding to requests, said Clinton officials at the time.