Sen. Cory Booker (D-N.J.) asked the Department of Justice on Wednesday to provide him with an internal document that could prove one of President Donald Trump’s picks for the federal bench lied to the Senate about his role in an effort to intimidate African-American voters.

Thomas Farr, who Trump tapped for a lifetime seat on the U.S. District Court for the Eastern District of North Carolina, served as a lawyer for the campaign of then-Sen. Jesse Helms (R-N.C.) in 1990. Shortly ahead of Election Day, the Helms campaign and Republicans sent out more than 100,000 postcards targeting African-Americans in the state. The postcards gave incorrect information about voter qualifications and falsely told voters that when they went to vote, they would have to tell polling officials how long they’d lived in their precinct. The postcards also said election fraud could be punished by up to five years in jail. The Department of Justice sued the campaign and the Republican Party, charging them with violating the Voting Rights Act. The parties eventually settled the case with a consent decree.

In September, Farr told the Senate as part of his confirmation hearing that he’d known nothing about the plan to send the postcards. But J. Gerald Hebert, a deputy chief in the voting section at the time, said he kept contemporaneous notes on the case that showed Farr had been consulted about the plan before it was executed. In a 1992 complaint, the Justice Department said the Helms campaign met in October 1990, before the postcards went out, to discuss ballot security ― and “an attorney who had been involved in past ballot security efforts on behalf of Senator Helms and/or the Defendant North Carolina Republican party” was there. Hebert says the attorney was Farr.

The Senate judiciary committee approved Farr’s nomination in October, but Hebert’s information, first reported by INDY Week, prompted calls for the committee to recall him for further questioning.

Booker asked Attorney General Jeff Sessions on Wednesday to provide him with a 1991 Justice Department memo containing the results of DOJ’s investigation into the postcard scheme and recommending whether to bring charges. Booker only wants the section of the memo outlining the facts of DOJ’s investigation, which could contain information about Farr’s possible involvement and knowledge of the postcards.

“It contains facts and legal arguments that support the filing of a lawsuit,” Booker wrote in the letter to Sessions. “It is clear to me that this memo is essential in determining whether Mr. Farr misled the Senate Judiciary Committee.”

Hebert told HuffPost that the 1991 memo “did exist and is likely in their files.” While he said DOJ was likely to redact the legal analysis, it has produced redacted memos showing the facts of an investigation in the past.

Booker also sent a letter to Farr Wednesday asking him to explain the discrepancies between his recollection and Hebert’s. The New Jersey Democrat asked Farr to provide more details on the work he did for the Helms campaign in 1990 as well as in 1984.

Gerald Hebert Notes from J. Gerald Hebert, a former Justice Department official, show that Thomas Farr may have known about a plan to send postcards targeting African-American voters earlier than he told the Senate.

The letters come amid continued scrutiny over Trump’s picks for the judiciary. On Tuesday, Sen. Chuck Grassley (R-Iowa), the chairman of the judiciary committee, told CNN he’d advised the White House to “reconsider” Trump’s nomination of Jeff Mateer for the federal bench in Texas, as well as Brett Talley for the judiciary in Alabama. Talley, who’s faced criticism for inflammatory online posts and failing to disclose to the Senate that his wife is a White House lawyer, reportedly offered to withdraw his nomination on Tuesday.

After Senate Republicans delayed confirming President Barack Obama’s nominees for the judiciary, Trump has moved swiftly to fill the federal judiciary with conservative judges. Because the judges receive lifetime appointments, it’s a legacy that will last long after Trump leaves office.

CORRECTION: An earlier version of this story said that Booker is a member of the Senate judiciary committee. He is not.

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