The investigation into Hunter Biden began in 2018, and became a central focus for then-president Donald Trump during his unsuccessful 2020 reelection effort. Initially, the investigation centered around Hunter Biden’s finances related to overseas business ties and consulting work. Over time, investigators with multiple agencies focused closely on whether he did not report all of his income, and whether he lied on gun purchase paperwork in 2018, according to the people familiar with the situation, who spoke on the condition of anonymity to discuss an ongoing case. -Washington Post.