US President Joe Biden's son Hunter pleaded not guilty to minor tax offenses Wednesday as a deal with federal prosecutors derailed in a Delaware court.
The surprise move came after Judge Maryellen Noreika raised questions over the original deal - under which Biden had agreed to enter a guilty plea and admit to illegal gun possession - and effectively placed it on hold.
Biden, 53, whose legal troubles have cast a shadow over his father's reelection campaign, had reached an agreement with prosecutors that he would be sentenced to probation on two tax avoidance counts.
The deal also specified that the firearms charge would eventually be erased if he adhered to a counseling-and-rehabilitation program.
But the deal fell apart after Noreika queried why the gun charge was included in a tax case, and whether the plea agreement protected Biden from charges that might arise from a wider ongoing investigation of his business dealings, according to US media.
When prosecutors could not resolve her questions, Noreika said she could not accept the deal, and Biden then entered a not guilty plea to close the session.
That was expected to send the deal back to negotiations, which could become more complex.
Prosecutor David Weiss confirmed to the court that his office is still examining other possible crimes by Biden.
Republicans have accused Weiss of giving Biden a "sweetheart deal" with the plea agreement announced on June 20.
White House Press Secretary Karine Jean-Pierre said Wednesday that Hunter Biden was "a private citizen. This was a personal matter."
The case was "handled independently by the Justice Department under the leadership of a prosecutor appointed by President Trump," she added.
The plea deal was to end a five-year investigation that Republicans have sought to use to politically harm his father Joe.
Maximum 10 years in jail
According to the charges, Hunter, a Yale-trained lawyer and lobbyist, failed to file his tax returns on time on earnings of more than $1.5 million for 2017 and 2018.
He was facing up to 12 months in prison for each tax charge and a possible maximum 10 years on a charge that, as a known drug user, he had illegally possessed a handgun in 2018.
But prosecutors recommended probation on the tax charges after Biden paid the taxes and penalties, according to his attorney.
In addition, the gun charge was to be suspended and then eliminated if Biden completed "pretrial diversion," which often involves counseling or rehabilitation.
That would require Biden to remain sober as the charges arise from a long period when he says he struggled with addiction.
"The president, the first lady, they love their son and they support him as he continues to rebuild his life," Jean-Pierre said.