Biden, a Democrat whose term ends on January 20 when Republican President-elect Donald Trump takes office, signed an unconditional pardon for Hunter Biden on Sunday and said he believed his son had been selectively prosecuted and targeted unfairly by the president's political opponents.
Biden had previously said he would not pardon his son, including to ABC News in June when he was asked if he would rule out a pardon, and replied "Yes".
Hunter Biden pleaded guilty in September to US federal tax charges in federal court in Los Angeles. (AP PHOTO)
His surprise move was panned by his Republican political opposition, but also by Democrats who say it threatens to undermine public trust in the rule of law, a concept Biden and his party has used to criticise Trump.
Hunter was prosecuted for tax offences and gun charges after being targeted for years by Republicans in Congress who accused him of making business deals using his father's name but failed to establish any clear connections.
White House spokeswoman Karine Jean-Pierre on Monday defended the president's action and said Biden believed Hunter faced further grief from his adversaries without naming them, and suggested it could continue even after the president left office.
Jean-Pierre was among the White House officials who had repeatedly said in the past Biden would not pardon his son.
"One of the reasons the president did the pardon is because they didn't seem like his political opponents would let go of it. It didn't seem like they would move on," she told reporters on Air Force One during a trip to Angola.
"They would continue to go after his son. That's what he believed."
Jean-Pierre stressed this was not the first time a president had pardoned a family member.
Bill Clinton pardoned his half-brother Roger before he left office, and Trump his daughter's father-in-law, Charles Kushner.
She said Biden believed in the Department of Justice despite his statement that his son's process in the judicial system was "infected with politics".
"Two things could be true: the president does believe in the justice ... system and ... Department of Justice, and he also believes that his son was singled out politically," she said.
She declined to give further details on why or how Biden had changed his mind, or whether the recent election that put Republicans in charge of the White House and both branches of Congress played a role.
That is false. As the President said last night, he made the decision this weekend. — Karine Jean-Pierre (@PressSec) https://t.co/CMifyPeKaCDecember 2, 2024
Republicans have accused Biden of corruption, while Democratic lawmakers have been split, with some suggesting he put family over country, and others pointing to Trump's nominees for judiciary positions as a rationale.
Hunter Biden pleaded guilty in September to federal tax charges in federal court in Los Angeles and was due to be sentenced on December 16.
A jury found him guilty in June of making false statements on a gun background check; he was due to be sentenced for those charges this month as well.
Biden on Sunday said his son had been selectively prosecuted and treated differently than others with similar situations.
"No reasonable person who looks at the facts of Hunter's cases can reach any other conclusion than Hunter was singled out only because he is my son - and that is wrong," he said.
Late on Sunday, Hunter Biden's lawyer filed to dismiss the indictments against him.
