President Biden’s son, Hunter Biden, is sitting for a closed-door deposition Wednesday with lawmakers as part of the House Republicans’ impeachment inquiry into the president.

Hunter Biden is the most crucial witness yet in the months-long probe, and the Republicans leading the investigation have long sought to interview him.

Republicans on the Oversight and Judiciary committees have placed Hunter Biden at the very center of their impeachment inquiry, alleging he engineered an elaborate web of lucrative, overseas business ventures that leaned heavily on his father’s international influence — and that the president himself has benefited financially from those shady arrangements.

But the White House and Hunter Biden’s legal team have vehemently denied the allegations and Republicans are still looking for a smoking gun.

Wednesday’s interview comes after the investigation suffered a blow with the arrest of an FBI informant on charges of fabricating a key allegation in the case.

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