PERSON: Joe Ziegler

Ziegler, who was known only as “Whistleblower X” before he testified to the House Oversight Committee on Wednesday, is a 13-year veteran of the IRS. He was the tax agency’s lead case agent in the federal investigation into Hunter Biden, which spanned both the Trump and Biden administrations.

“I’m a Democrat. In the last presidential election, I actually did not vote,” Ziegler told CBS News in an interview. “I thought it would be irresponsible of me to do so because I didn’t want to show bias one way or the other.”

He said he recommended prosecutors charge Hunter Biden with multiple felonies and misdemeanors in 2021. Among the allegations is that Ziegler believed he had evidence that showed the president’s son had improperly claimed business deductions for a number of personal expenses, including his children’s college tuition, hotel bills and payments to escorts.

Hunter Biden’s legal team did not immediately respond to a request for comment.

Ziegler compared the weight of testifying to Congress about the investigation to his experience of coming out as gay, which he called “one of the hardest things I ever had to do.”

“I hope that I am an example to other LGBTQ people out there, who are questioning doing the right thing at a potential cost to themselves and others,” his opening statement said.

Prior to his employment at the IRS, Ziegler worked as an external auditor for Ernst and Young. He graduated from Ohio University with an accounting degree and then went on to earn a master’s in business administration from John Carroll University.

He said he has worked on criminal tax and money laundering cases throughout his IRS career, including being the lead case agent on an investigation involving a major social media company and another involving a billionaire.

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