In a recent revelation, President Joe Biden was reportedly "extremely well known" to federal authorities investigating his son, Hunter Biden. The President even made an appearance at an FBI office during the probe, according to IRS special agent Joseph Ziegler, who was assigned to the case.

Ziegler's testimony before the House Oversight Committee highlighted the challenges of conducting the investigation in Delaware, a state where the Biden family is well-known. He noted that the President's visit to the FBI office was joked about within the team. Furthermore, a Delaware magistrate judge had to recuse herself from the investigation due to inappropriate comments made during the signing of the first electronic search warrant. This setback delayed the investigation by an additional four months as new warrants had to be drafted and investigative steps repeated.

The investigation also suffered a significant blow when one of its top prosecutors, Assistant US Attorney Jamie McCall, left for the private sector in early 2020. Ziegler described McCall as a "hard-working, no-nonsense kind of AUSA" who was committed to doing the right thing.

The IRS whistleblowers, Ziegler and his supervisor, Gary Shapley, reiterated their previous testimony to the House Ways and Means Committee, alleging that the Justice Department under President Biden slow-walked the five-year probe into Hunter Biden's alleged financial crimes. They claimed that Biden-appointed US attorneys interfered in the case, preventing Delaware US Attorney David Weiss from charging Hunter Biden with tax fraud last year in Southern California and Washington, DC.

However, both Weiss and Attorney General Merrick Garland have denied these allegations, asserting that Weiss had the authority to bring any charges he deemed necessary.

The IRS agents also claimed that federal authorities tipped off Hunter's legal team about a potential search of his northern Virginia storage locker and a December 2020 effort to interview him, thereby preventing either from being carried out. They further alleged that attempts to inquire about the President's involvement in his son's overseas business deals and seek felony charges for $2.2 million in missed tax payments were thwarted.

The agents also obtained a WhatsApp message from July 30, 2017, in which Hunter invoked his father's name to pressure a Chinese businessman into reportedly paying around $5 million to him and his associates.

Shapley and Ziegler, who have identified their registered political affiliations as Republican and Democrat, respectively, have both served for more than a decade at the IRS. They emphasized that their whistleblowing had no personal benefit and was solely in the interest of transparency and justice.

On June 20, Weiss' office announced that Hunter had entered into a probation-only plea deal for two tax misdemeanors and a diversion agreement for a firearms charge. The first son had avoided six-figure tax payments in 2017 and 2018 and lied on a federal gun-purchase form in 2018 about drug use while he was addicted to crack cocaine.