Joe Biden will not pardon his son Hunter on tax- and gun-related charges, the White House said on Thursday. At a briefing, the press secretary, Karine Jean-Pierre, was asked: “From a presidential perspective, is there any possibility that the president would end up pardoning his son?” “No,” Jean-Pierre replied. Pressed, she said: “I just said no. I answered.” In court in Wilmington, Delaware, on Wednesday, Hunter Biden pleaded not guilty to two tax charges, both misdemeanours. He had been expected to plead guilty as part of a deal with federal prosecutors also including a pre-trial diversion program on the guns charge, a felony. In the event, a question from the judge about the scope of the deal led to its delay. Republicans claim Hunter Biden’s business affairs, and personal problems including public struggles with addiction, show Joe Biden to be corrupt and worthy of impeachment. Rightwingers have long cried foul over the younger Biden’s treatment by federal authorities. The pardon power is established in article 2 of the US constitution, which says the president “shall have power to grant reprieves and pardons for offences against the United States, except in cases of impeachment”. The use of the pardon power has become increasingly controversial, presidents including Bill Clinton and Donald Trump having bestowed pardons and acts of clemency on donors and supporters. Trump was widely reported to have considered whether he could pardon himself, on issues including alleged collusion with Russian interference in the 2016 election. Trump also reportedly explored the idea of giving pre-emptive pardons to family members, another step he did not ultimately take. Now, Trump faces 71 criminal indictments and the prospect of more. As he seeks the Republican presidential nomination in 2024, most observers expect his lawyers to seek to draw out such legal battles in the hope he or another Republican in the White House will seize the pardon power. State-level indictments, however, are not subject to presidential pardons. In New York, Trump faces 34 criminal charges over hush-money payments to a porn star during the 2016 election. In Georgia, he is expected to be indicted over his election subversion in 2020. On Wednesday, Jean-Pierre told reporters Hunter Biden was “a private citizen”, and called his legal problems “a personal matter for him”. “As we have said, the president [and] the first lady, they love their son, and they support him as he continues to rebuild his life. This case was handled independently, as all of you know, by the justice department under the leadership of a prosecutor appointed by the former president.” Biden has used the pardon power sparingly, focusing largely on convictions for offenses relating to drugs. In four years in office, Trump issued 143 pardons and 94 commutations. Many were highly controversial, including pardons for his advisers Steve Bannon, Roger Stone and Paul Manafort. The Pew Research Center, however, points out that an analysis of justice department data shows Trump “used his executive clemency power less frequently than nearly every other president since the turn of the 20th century”.