Senate Democrats are using the Freedom of Information Act to try to force the National Archives to release more documents relating to Supreme Court nominee Brett Kavanaugh.

Senate Minority Leader Chuck Schumer, D-N.Y., said if the documents are not produced within 20 days, Democrats plan to sue the federal government.

Schumer said lawmakers will issue FOIA requests to nine departments of the National Archives “seeking the full gamut of Kavanaugh’s records including his time as staff secretary” to former President George W. Bush.

Schumer accused Republicans of blocking the release of the all the documents relevant to Kavanaugh’s nomination. Kavanaugh, now a judge on the D.C. Court of Appeals, served as staff secretary for Bush from 2003 until 2006.

“We stand ready to sue the National Archives for Judge Kavanaugh’s full records if necessary,” Schumer said.

Sen. Richard Blumenthal, D-Conn., a key member of the Senate Judiciary Committee, said Democrats need the documents to adequately review Kavanaugh’s nomination.

The judiciary panel will hold a confirmation hearing on Kavanaugh on Sept. 4.

Blumenthal accused the GOP of concealing Kavanaugh’s records in a way that was “unprecedented, and literally hiding documents ” about his career.

[Related: Senate Democrats push for all Kavanaugh records: 'What are they hiding?']

Blumenthal said the National Archives is able to expedite production of the papers, although officials said much of the paperwork already requested by Judiciary Committee Chairman Chuck Grassley, R-Iowa, won’t be ready until the end of October.

Democrats see a more sinister reason for the delay.

“The question really here is: What are they afraid of the American people seeing?” Blumenthal said.

Democrats are also opposed to the “committee confidential” label placed on many of the Kavanaugh documents that will be provided.

“It is not enough that the committee see these documents, but the American people have a right as well,” Blumenthal said.

Republicans are largely ignoring the demands of the Democrats. They say Democrats are attempting to stall a high court nomination they have no power to block because they are in the minority.

About a half million documents stem from Kavanaugh’s time as a Bush staff secretary and have little to do with his nomination, Majority Whip John Cornyn, R-Texas, said, because he did not create or have input into the papers.

“Those don’t really have any relevance to his experience or qualifications to serve as a judge,” Cornyn said.

Grassley said the Judiciary Committee will have access to several hundred thousand pages of documents, including hundreds of opinions written by Kavanaugh during a dozen years serving as a federal judge.

He said providing all of the documents Democrats are demanding would require turning over “every scrap of paper of the Bush presidency.”