Then-Trump campaign chairman Paul Manafort talks to reporters at the Republican National Convention in Cleveland in July 2016. (Matt Rourke/AP)

Attorneys for Paul Manafort have asked a federal judge to bar prosecutors from presenting evidence at his Washington trial this fall from one of his previous lawyers, evidence that may be critical to proving charges he gave false statements under a federal lobbying disclosure law.

There is no grand jury transcript of the attorney’s testimony, Manafort’s legal team said in filings late Monday night, because prosecutors interviewed the attorney outside of the grand jury after the chief justice of the federal court in Washington said the attorney could be called to testify in the probe by special counsel Robert S. Mueller III.

“As a result, Mr. Manafort is unable to determine the exact nature of that testimony,” attorneys Kevin M. Downing, Thomas E. Zehnle and Richard W. Westling wrote while reviving an argument, previously rejected by the chief judge, that the lawyer’s advice and legal work for Manafort was confidential and shielded by attorney-client privilege.

The lawyer helped Manafort file forms with the U.S. Justice Department about work on behalf of foreign interests that are required by the Foreign Agents Registration Act.

The criminal counts in Manafort’s case in the District include that he “knowingly and willfully caused to be made a false statement’’ in a FARA-required filing.

The objection to the attorney’s testimony was part of a seven-page filing to the Washington trial judge that repeated many of the requests Manafort’s legal team raised Friday before a federal judge in Alexandria, Va., where he also faces trial.

One motion they did not echo Monday was for a change of venue. Manafort’s trial in Washington on lobbying, conspiracy and witness tampering is set to start Sept. 17.

His trial in Alexandria is scheduled to begin July 25 on bank and tax fraud and his attorneys have asked to move that proceeding to Roanoke, saying a more Republican-friendly jury would decide his guilt or innocence more fairly.

Manafort, 69, has pleaded not guilty to all charges in both federal courts.

Before Manafort was indicted Oct. 27 in Washington, Mueller obtained a ruling by Chief U.S. District Judge Beryl A. Howell of the District compelling his former lawyer to testify.

Attorney-client privilege is a bedrock principle of U.S. legal practice that says a lawyer must keep confidential what they are told by their clients.

There are some exceptions however, including instances in which a suspect may have lied to his or her lawyer, causing that lawyer to unwittingly lie to the government. Howell ruled that in Manafort’s case, the “crime-fraud” exception applied and the lawyer could be called to testify before the grand jury.  

In the filings Monday, Manafort’s lawyers said it was “puzzling” that while Howell upheld the grand jury’s subpoena, the questioning of the attorney was ultimately undertaken by Mueller’s team, outside of the presence of the grand jury. They added that Manafort’s defense was not part of the process.

Manafort’s attorneys asked the trial judge in his case — U.S. District Judge Amy Berman Jackson — to hold a sealed hearing to let them challenge prosecutors’ assertions that the crime-fraud exception should apply before she decides whether to admit the evidence at trial.

A reply from Mueller’s office was expected but had not immediately been filed with the court.

The lawyer ordered to testify is not identified in public court filings but previously has been identified by people familiar with the case as Melissa Laurenza.

Laurenza and a spokesman for her law firm did not immediately respond to emails seeking comment.

The filing to the Washington judge repeated requests Manafort’s lawyers made in Alexandria: They want to bar any reference to one trial at the other; bar any mention that Manafort was jailed awaiting trial after being accused of attempting to sway witnesses while he was on bail; and bar any reference to Manafort’s role in the Trump campaign and the special counsel’s investigation of the campaign’s alleged collusion with the Russian government.

Earlier Monday, prosecutors for their part had asked Jackson to bar Manafort from arguing at his District trial that he was singled out for prosecution because of his campaign role.

They also said asked that Manafort be barred from suggesting that any previous government investigation ended with a decision not to prosecute him, a notion they called wrong and misleading.

Mueller’s office argued Manafort already had his chances to raise those issues to judges before trials were set and that the sole question for jurors is whether “the defendant actually committed the crimes” charged, prosecutor Andrew Weissmann wrote.

Manafort had previously challenged the scope of the special counsel’s authority and appointment and asked to have his federal cases in the District and Virginia tossed. He lost those motions.