The House approved contempt charges against White House officials Thursday, implementing a two-pronged strategy that allows the chamber to pursue the matter in both criminal and civil court.

In a lopsided vote that included almost no Republicans — who boycotted the vote over objections to unrelated legislation — the measure passed 223-32.

“This is not a conflict that Congress has sought,” Speaker Nancy Pelosi (D-Calif.) asserted on the House floor. She later added: “Congress has the responsibility of oversight of the executive branch. I know that Members on both sides of the aisle take that responsibility seriously.”

The House issued contempt citations against former White House counsel Harriet Miers and White House Chief of Staff Joshua Bolten in July 2007, after seeking to compel documents and testimony from them in their probe stemming from the suspicious firing of nine federal prosecutors in 2006. (The Senate also has issued a contempt citation in the matter against Bolten, as well as ex-White House political guru Karl Rove.)

Under the measure approved Thursday, the Speaker will refer the House citations to the U.S. Attorney’s Office for the District of Columbia with the expectation that the office would impanel a grand jury.

Should the U.S. attorney refuse to do so, however, Democrats could trigger the second half of their strategy, which grants the House Judiciary Committee standing to proceed to civil litigation on the matter.

In that scenario, a judge could rule on the legitimacy of the Bush administration’s claims of executive privilege and potentially order Miers and Bolten to testify. White House counsel Fred Fielding has asserted conversations between President Bush and Miers and Bolten are protected, and offered the aides for only informal interviews without transcripts and not under oath.

Pelosi said she hoped the Thursday action would prompt the White House to reach an equitable agreement with the House, rather than the lengthy legal fight that is expected.

But she added: “Through this resolution, [we] have the power ourselves to go to the federal court and seek civil enforcement of our subpoenas.”

Republicans criticized the majority’s decision to take action on the citations, asserting that the House should instead focus on an expansion of the federal wiretapping law approved by the Senate earlier this week.

“We should be doing the nation’s business with respect to that, rather than this,” said Rep. Dan Lungren (R-Calif.)

House Republicans subsequently staged a walkout Thursday afternoon in protest against Democratic leaders.

On the East Front steps, Minority Leader John Boehner (R-Ohio) said House Republicans are prepared to stay in Washington until the FISA bill gets done.

“Putting politics first and national security second is just not good enough,” Minority Whip Roy Blunt (R-Mo.) said, referring to the Democrats’ contempt vote on the floor.

House Intelligence ranking member Pete Hoekstra (Mich.) argued that failing to act by Saturday will not only put Americans at greater risk but also endanger American troops and allies around the world.

A few dozen Republicans returned to the chamber, however, the majority of whom voted against the contempt measures.

Lauren W. Whittington contributed to this report.