(Bloomberg) -- Hunter Biden and his legal team want to subpoena former President Donald Trump, former Attorney General William Barr and others, saying they applied improper political pressure on the federal investigation and prosecution of him.

Trump, Barr and others appeared to use “incessant, improper, and partisan pressure” on federal prosecutors to investigate President Joe Biden’s son, according to a filing Wednesday by Hunter Biden’s lawyers in federal court in Delaware. They asked the court to issue the subpoenas.

The request is another sign that Hunter Biden and his lawyers are going on the offensive in response to the Justice Department’s investigation into him, which resulted in an indictment over federal firearm violations. The probe is continuing and a special counsel appointed by Attorney General Merrick Garland to lead it is expected to also charge him with tax crimes.

Along with Trump and Barr, subpoenas also are being sought for Jeffrey Rosen, who served as deputy attorney general under Barr and took over as acting attorney general when Barr stepped down in December 2020. A subpoena is also being sought for another former Justice Department official, Richard Donoghue.

The subpoenas would compel Trump and the others to turn over all documents, including communications, about the Hunter Biden investigation and prosecution decisions by Dec. 1.

Barr declined to comment. Rosen and Donoghue and a spokesman for Trump didn’t immediately respond to requests for comment. 

The complaint cited examples of how Trump “improperly and unrelentingly pressured” the Justice Department to pursue Hunter Biden, calling for law enforcement, the media and the public to “go after” him.

It quoted Barr’s recent book citing a call he received in mid-October 2020 in which Trump asked him about the Hunter Biden investigation. Barr wrote that he responded: “Dammit, Mr. President, I am not going to talk to you about Hunter Biden. Period!”

It also cited notes that then-Deputy Attorney General Donoghue took in late December 2020 of a call in which Trump insisted “people will criticize the DOJ if he’s not investigated for real.”

In one Truth Social post this year, Trump said Biden should receive a “death sentence.”

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