House Democrats and the White House moved closer to a constitutional showdown Monday when Rep. John Conyers Jr. (D-Mich.) readied a contempt-of-Congress citation against the White House for failing to comply with subpoenas for documents and testimony from two top staffers.

Conyers, chairman of the House Judiciary Committee, filed the contempt resolution with the clerk of the House Monday. But he gave the administration one last chance to comply with subpoenas for documents and testimony from White House Chief of Staff Josh Bolten and former White House Counsel Harriet Miers.

“As we submit the committee’s contempt report to the full House, I am writing one more time to seek to resolve this issue on a cooperative basis,” wrote Conyers. He asked Fielding to respond by Friday.

The move does not necessarily mean the House will vote on the contempt citation, but it gives Democratic leaders the option to bring up the resolution should they decide to pursue it.

If Democrats pass the measure and the White House continues to assert executive privilege to deny them access to discussions between presidential and vice presidential aides, a constitutional showdown between the two branches could reach the Supreme Court.

However, it remains unclear if Democrats have the votes to pass the resolution. The vast majority of Republicans would likely vote against it on the floor.

Bolten and Miers were subpoenaed earlier this year as part of the Democrats’ ongoing investigation into the U.S. attorney firings. Democrats are trying to find out whether politics played an improper role in the prosecutors’ dismissals and what role, if any, White House officials played in their ousters. On a party-line vote, the Judiciary Committee passed contempt resolutions against Miers and Bolten at the end of July after they did not respond to subpoenas issued earlier this year.

Democrats want the White House to provide the Judiciary Committee with copies of documents relating to communications between White House staff and others outside the White House regarding the U.S. attorney firings.

White House spokeswoman Dana Perino ridiculed the Democratic congressional leadership for spending so much time investigating the White House when they still have a string of appropriations bill to pass.

“I’m just amazed that the Democrats actually think they’ve accomplished so much on behalf of the American people that they can now waste time again on another diversion,” Perino told reporters at the White House daily briefing.

Perino noted that House Democrats named conferees on the labor, health and human services and education appropriations bill only just last week, the first time they had moved to conference a spending bill this year.

She also said Democrats had repeatedly turned down the White House offer of interviews with senior staff — although she conceded the White House refused to have the interviews take place under oath or have them transcribed.

“We have turned over thousands of pages of documents, many people have testified, hundreds of hours of testimony on this issue regarding U.S. attorneys,” she said. “And so while they failed to pass legislation that’s important to the American people, they move forward with this contempt citation.”

House Republicans on the Judiciary Committee immediately derided Conyers’s decision to file the contempt citation as a waste of time after an exhaustive investigation into the U.S. firings that included 15 hearings, meetings and mark-ups regarding the U.S. attorney removals, a dozen witness interviews with Justice Department officials and a review of more than 10,000 pages of documents released by the administration.

Republicans also highlighted Democrats’ decision to spend $250,000 to hire Arnold & Porter to help run the U.S. attorneys investigation. House Speaker Nancy Pelosi (D-Calif.) recently named Irv Nathan, a partner at the firm involved in the Judiciary panel investigation, to be the new House counsel whose job it would be to pursue the contempt case in court.

Rep. Lamar Smith (Texas), the ranking Republican on the Judiciary Committee, said, “Today’s filing is a desperate attempt by Democrats to distract attention from their poor record in Congress.”

House Minority Leader John Boehner (R-Ohio) also weighed in, arguing that the U.S. attorneys investigation “failed to produce any results” even though the Democrats on the panel spent “more time playing political games on this issue than it has spent on national security, violent crime and sexual predators combined.”