Biden's Ukraine trip coincided with meeting Hunter and Rosemont Seneca executives.

Hunter Biden and his business partners with ties to Burisma attended a December 2015 holiday party hosted by then-Vice President Joe Biden just a few days after he returned from his trip to Ukraine, where he threatened to withhold $1 billion in U.S. aid if the country’s leaders did not fire their top prosecutor. Biden's defenders have said that the prosecutor was fired not because he was pursuing corruption too aggressively, but rather because he was too lax. The elder Biden was photographed at the party, and Hunter and several of his business partners from his now-dissolved investment firm Rosemont Seneca Partners were also in attendance. Days before the party and Biden's Ukraine trip, several emails were exchanged between Hunter and his partners about Burisma, including deliberations about how to respond to media inquiries about Hunter’s involvement with the Ukrainian company.