A federal judge ordered the man who set up Hillary Clinton’s private email server Friday to produce the immunity agreement he had reportedly struck with the Department of Justice as part of her investigation.

According to The Hill, the judge’s order postpones Bryan Pagliano’s deposition with the watchdog group Judicial Watch indefinitely. The interview had been scheduled to take place Monday.

Pagliano planned to assert his Fifth Amendment rights against self-incrimination and refuse to answers questions over an open records lawsuit, according to court documents obtained Wednesday by Fox News. His lawyers also asked a federal judge to block Judicial Watch from recording his deposition, stating that a written transcription should be enough.

However, Judge Emmet Sullivan declared that his lawyers need to file a legal memorandum to outline the legality for him to plead the Fifth “including requisite details pertaining to the scope of Mr. Pagliano's reported immunity agreement with the government,” The Hill reported.

Tom Fitton, the president of Judicial Watch, called Sullivan’s order “an important step to getting more answers from Mr. Pagliano about Hillary Clinton's email system.”

Pagliano, who worked on Clinton’s 2008 presidential campaign before helping install the so-called “homebrew” server system in her Chappaqua, N.Y. home, cut an immunity deal last fall with the Justice Department amid the FBI probe. He was recently described to Fox News by an intelligence source as a “devastating witness.”

In the fall, Pagliano told at least three congressional committees in the fall that he will invoke the Fifth Amendment to avoid testifying against Clinton. He was asked to testify about the serve by the House Select Committee on Benghazi, the Senate Judiciary Committee and the Senate Homeland Security Committee.

The Washington Post reported in September 2015 that Pagliano had been subpoenaed by the Benghazi committee Aug. 11 and committee chairman Rep. Trey Gowdy, R-S.C. had ordered that he appear for questioning Sept. 10. Gowdy also demanded that Pagliano provide documents related to all servers or computer systems controlled or owned by Clinton between 2009 and 2013.

The Post reported in August 2015 that Pagliano had worked as an IT director on Clinton’s 2008 presidential campaign, and was asked to oversee the installation of Clinton’s server to handle her correspondence while secretary of state. He was paid by a political action committee tied to Clinton until April 2009, when he was hired by the State Department as an IT specialist.

According to the paper, Pagliano left government service in February 2013 and now works for a technology contractor that provides some services for the State Department.

Lawyers for senior Clinton aide Cheryl Mills, during a nearly five-hour deposition last week in Washington, repeatedly objected to questions about Pagliano’s role in setting up the former secretary of state’s private server.

According to a transcript of the deposition with Judicial Watch released on Tuesday, Mills attorney Beth Wilkinson – as well as Obama administration lawyers – objected to the line of questioning about Pagliano, who has emerged as a central figure in the FBI's ongoing criminal probe of Clinton's email practices.

Clinton, the Democratic presidential frontrunner, has repeatedly denied any wrongdoing related to her private server.

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