President Joe Biden pardoned his son, Hunter, sparing the younger Mr. Biden a possible prison sentence for federal felony gun and tax convictions and reversing his past promises not to use the extraordinary powers of the presidency for the benefit of his family.

The Democratic president had previously said he would not pardon his son or commute his sentence after convictions in the two cases in Delaware and California. The move on the night of Dec. 1 comes weeks before Hunter Biden was set to receive his punishment after his trial conviction in the gun case and guilty plea on tax charges, and less than two months before President-elect Donald Trump is set to return to the White House.

It caps a long-running legal saga for the younger Mr. Biden, who publicly disclosed he was under federal investigation in December 2020 – a month after his father’s 2020 victory – and casts a pall over the elder Mr. Biden’s legacy.

Mr. Biden, who time and again pledged to Americans that he would restore norms and respect for the rule of law after Mr. Trump’s first term in office, ultimately used his position to help his son, breaking his public pledge to Americans that he would do no such thing.

In a statement released the evening of Dec. 1, Mr. Biden said, “I believe in the justice system, but as I have wrestled with this, I also believe raw politics has infected this process and it led to a miscarriage of justice.”

The president’s sweeping pardon covers not just the gun and tax offenses against the younger Mr. Biden, but also any other “offenses against the United States which he has committed or may have committed or taken part in during the period from January 1, 2014 through December 1, 2024.”

In June, Mr. Biden categorically ruled out a pardon or commutation for his son, telling reporters as his son faced trial in the Delaware gun case, “I abide by the jury decision. I will do that and I will not pardon him.”

As recently as Nov. 8, days after Mr. Trump’s victory, White House press secretary Karine Jean-Pierre ruled out a pardon or clemency for the younger Mr. Biden, saying, “We’ve been asked that question multiple times. Our answer stands, which is no.”

The elder Mr. Biden has publicly stood by his only living son as Hunter descended into serious drug addiction and threw his family life into turmoil before getting back on track in recent years. The president’s political rivals have long used Hunter Biden’s myriad mistakes as a political cudgel against his father: In one hearing, lawmakers displayed photos of the drug-addled president’s son half-naked in a seedy hotel.

House Republicans also sought to use the younger Mr. Biden’s years of questionable overseas business ventures in a since-abandoned attempt to impeach his father, who has long denied involvement in his son’s dealings or benefiting from them in any way.

“The charges in his cases came about only after several of my political opponents in Congress instigated them to attack me and oppose my election,” Mr. Biden said in his statement. “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.”

“I hope Americans will understand why a father and a President would come to this decision,” Mr. Biden added, claiming he made the decision this weekend.

The president had spent the Thanksgiving holiday in Nantucket, Massachusetts, with Hunter and his family, and departed for Angola later Dec. 1 on what may be his last foreign trip as president before leaving office on Jan. 20, 2025.

Hunter Biden was convicted in June in Delaware federal court of three felonies for purchasing a gun in 2018 when, prosecutors said, he lied on a federal form by claiming he was not illegally using or addicted to drugs.

He had been set to stand trial in September in the California case accusing him of failing to pay at least $1.4 million in taxes. But he agreed to plead guilty to misdemeanor and felony charges in a surprise move hours after jury selection was set to begin.

David Weiss, the Trump-appointed U.S. attorney in Delaware who negotiated the plea deal, was subsequently named a special counsel by Attorney General Merrick Garland to have more autonomy over the prosecution of the president’s son.

Hunter Biden said he was pleading guilty in that case to spare his family more pain and embarrassment after the gun trial aired salacious details about his struggles with a crack cocaine addiction.

The tax charges carry up to 17 years behind bars and the gun charges are punishable by up to 25 years in prison, though federal sentencing guidelines were expected to call for far less time and it was possible he would have avoided prison time entirely.

Hunter Biden was supposed to be sentenced this month in the two federal cases, which the special counsel brought after a plea deal with prosecutors that likely would have spared him prison time fell apart under scrutiny by a judge. Under the original deal, Hunter was supposed to plead guilty to misdemeanor tax offenses and would have avoided prosecution in the gun case as long as he stayed out of trouble for two years.

But the plea hearing quickly unraveled last year when the judge raised concerns about unusual aspects of the deal. The younger Mr. Biden was subsequently indicted in the two cases.

Hunter Biden’s legal team this weekend released a 52-page white paper titled “The political prosecutions of Hunter Biden,” describing the president’s son as a “surrogate to attack and injure his father, both as a candidate in 2020 and later as president.”

The younger Mr. Biden’s lawyers have long argued that prosecutors bowed to political pressure to indict the president’s son amid heavy criticism by Mr. Trump and other Republicans of what they called the “sweetheart” plea deal.

Rep. James Comer, one of the Republican chairmen leading congressional investigations into Mr. Biden’s family, blasted the president’s pardon, saying that the evidence against Hunter was “just the tip of the iceberg.”

“It’s unfortunate that, rather than come clean about their decades of wrongdoing, President Biden and his family continue to do everything they can to avoid accountability,” Comer said on X, the website formerly known as Twitter.

Mr. Biden is hardly the first president to deploy his pardon powers to benefit those close to him.

In his final weeks in office, Mr. Trump pardoned Charles Kushner, the father of his son-in law, Jared Kushner, as well as multiple allies convicted in special counsel Robert Mueller’s Russia investigation. Mr. Trump over the weekend announced plans to nominate the elder Mr. Kushner to be the U.S. envoy to France in his next administration.

Mr. Trump, who has pledged to dramatically overhaul and install loyalists across the Justice Department after he was prosecuted for his role in trying to subvert the 2020 presidential election, said in a social media post on Dec. 1 that Hunter Biden’s pardon was “such an abuse and miscarriage of Justice.”

“Does the Pardon given by Joe to Hunter include the J-6 Hostages, who have now been imprisoned for years?” Mr. Trump asked, referring to those convicted in the violent Jan. 6, 2021 riot at the U.S. Capitol by his supporters.

Hunter Biden said in an emailed statement that he will never take for granted the relief granted to him and vowed to devote the life he has rebuilt “to helping those who are still sick and suffering.”

“I have admitted and taken responsibility for my mistakes during the darkest days of my addiction – mistakes that have been exploited to publicly humiliate and shame me and my family for political sport,” the younger Mr. Biden said.

Hunter Biden’s legal team filed the night of Dec. 1 in both Los Angeles and Delaware asking the judges handling his gun and tax cases to immediately dismiss them, citing the pardon.

A spokesperson for Mr. Weiss did not respond to messages seeking comment the night of Dec. 1.

NBC News was first to report Mr. Biden was expected to pardon his son on Dec. 1.

This story was reported by The Associated Press. AP writer Josh Boak contributed to this report.