IRS whistleblowers to testify behind closed doors amid Biden impeachment inquiry

The IRS whistleblowers who allege the federal investigation into Hunter Biden has been influenced by politics are testifying before the House Ways and Means Committee behind closed doors Tuesday.

Gary Shapley, who led the IRS’ portion of the Hunter Biden probe, and Joseph Ziegler, a 13-year special agent within the IRS’ Criminal Investigation Division, will sit for a closed-door hearing during the committee’s executive session Tuesday at 10:30 a.m.

IRS OFFICIAL SAYS HE WAS FRUSTRATED DOJ DID NOT BRING CHARGES AGAINST HUNTER BIDEN FOR 2014, 2015 TAX YEARS

The whistleblowers are set to discuss information "protected under Internal Revenue Code Section 6103," according to the committee, meaning the information is related to confidentiality of tax returns.

Supervisory IRS Special Agent Gary Shapley, left, and IRS Criminal Investigator Joseph Ziegler are sworn-in as they testify during a House Oversight Committee hearing related to the Justice Department's investigation of Hunter Biden. (Drew Angerer/Getty Images)

Shapley and Ziegler have alleged political influence surrounding prosecutorial decisions throughout the Hunter Biden investigation, which began in 2018.

Shapley has said that decisions "at every stage" of the probe were made that "had the effect of benefiting the subject of the investigation."

And Ziegler has said that Hunter Biden "should have been charged with a tax felony, and not only the tax misdemeanor charge" and that communications and text messages reviewed by investigators "may be a contradiction to what President Biden was saying about not being involved in Hunter’s overseas business dealings."

House Ways and Means Chairman Jason Smith (Bill Clark/CQ-Roll Call, Inc via Getty Images)

Ziegler also alleged that federal investigators "did not follow the ordinary process, slow-walked the investigation, and put in place unnecessary approvals and roadblocks from effectively and efficiently investigating the case," including prosecutors blocking certain questioning and interviewing of Hunter Biden’s adult children.

COMER, JORDAN DEMAND HUNTER BIDEN APPEAR FOR DEPOSITION, SAY HE WILL NOT RECEIVE 'SPECIAL TREATMENT'

Shapley also said U.S. Attorney for Delaware David Weiss, who was leading the investigation, requested special counsel authority but was denied and said that he did not have "ultimate authority" in the probe to pursue charges against the president's son.

Weiss was tapped as special counsel by Attorney General Merrick Garland in August.

Weiss, during his interview before the House Judiciary Committee last month, admitted he initially "wasn’t granted" special attorney authority in his Hunter Biden investigation by the Justice Department despite requesting that status, but he told investigators he did not interpret that decision as a "denial in any way, shape or form," according to a transcript of his testimony reviewed by Fox News Digital.

The closed session at Ways and Means is set to take place a week before Assistant U.S. attorney Lesley Wolf is set to be deposed by the House Judiciary Committee after being subpoenaed last month.

Her deposition, set for Dec. 14, comes after Shapley alleged Wolf sought to block investigators from asking questions related to President Biden throughout the years-long federal investigation into Hunter Biden.

United States President Joe Biden's son, Hunter Biden, exits the J. Caleb Boggs Federal Building in Delaware, United States on July 26, 2023. (Celal Gunes/Anadolu Agency via Getty Images)

Specifically, Shapley alleged Wolf worked to "limit" questioning related to President Biden and apparent references to Biden as "dad" or "the big guy."

Wolf allegedly said there was "no specific criminality to that line of questioning" relating to President Biden, which Shapley said "upset the FBI."

COMER DEFENDS PRIVATE DEPOSITION OF HUNTER BIDEN, VOWS TO RELEASE TRANSCRIPT AND HOLD PUBLIC HEARING

In October 2020, Wolf reviewed an affidavit for a search warrant of Hunter Biden’s residence and "agreed that probable cause had been achieved," Shapley testified. However, Shapley said Wolf ultimately would not allow a physical search warrant on the president’s son.

Shapley said Wolf determined there was "enough probable cause for the physical search warrant there, but the question was whether the juice was worth the squeeze."

Rep. Jim Jordan, R-Ohio, chairman of the House Judiciary Committee (Tom Williams/CQ-Roll Call, Inc via Getty Images)

Wolf allegedly said that "optics were a driving factor in the decision on whether to execute a search warrant," Shapley said, adding that Wolf agreed that "a lot of evidence in our investigation would be found in the guest house of former Vice President Biden, but said there is no way we will get that approved."

Wolf also allegedly tipped off Hunter Biden’s legal team ahead of a planned search of his storage unit, Shapley said.

MONEY LAUNDERING INVESTIGATOR WARNED OF HUNTER BIDEN'S 'UNUSUAL,' 'ERRATIC' PAYMENTS FROM CHINA IN 2018

The whistleblowers’ testimony at Ways and Means and Wolf’s deposition at Judiciary comes as part of the House impeachment inquiry against President Biden.

House Ways and Means Committee Chairman Jason Smith, R-Mo., Judiciary Committee Chairman Jim Jordan, R-Ohio, and Oversight Committee Chairman James Comer, R-Ky., are leading the investigation as the House gathers evidence and considers whether to draft articles of impeachment against President Biden.

James Comer, R-Ky. (Tom Williams/CQ-Roll Call, Inc via Getty Images)

The committees are investigating the alleged politicization of the federal probe into Hunter Biden. They are also investigating the Biden family’s foreign business dealings and whether the president was involved or benefited directly from those ventures.

President Biden has repeatedly denied having any involvement in his son’s business dealings.

Hunter Biden has been charged with making a false statement in the purchase of a firearm; making a false statement related to information required to be kept by a federal firearms licensed dealer; and one count of possession of a firearm by a person who is an unlawful user of or addicted to a controlled substance.

President Biden speaks in the State Dining Room of the White House on Oct. 10, 2023. (Ting Shen/Bloomberg via Getty Images)

Hunter Biden pleaded not guilty in October.

Weiss' investigation is ongoing.

Hunter Biden was subpoenaed to appear for a deposition at the House Oversight Committee on Dec. 13.

Brooke Singman is a Fox News Digital politics reporter. You can reach her at This email address is being protected from spambots. You need JavaScript enabled to view it. or @BrookeSingman on Twitter.