The judge raised constitutional issues about the gun diversion agreement.
The judge indicated that she would schedule a future hearing, essentially putting the plea deal on hold.
Bidens attorneys believed that the plea deal would mean that he would not face future charges.
Hunter Biden arrives at the federal courthouse in Wilmington, DE in July.(Photo by Anna Moneymaker/Getty Images)
The terms of the deal were revealed last month in a letter that U.S. AttorneyDavid Weisssent to the judge.
Biden will plead guilty to two counts of failure to pay federal income tax.
Bidens legal team said that the plea agreement meant that potential charges were foreclosed.
Both sides are continuing to meet, but the unexpected turn dominated the morning news cycle.
But after an hour, word came from reporters in the courtroom that the deal was in doubt.
The Justice Department has offered to make Weiss available to testify before the House Judiciary Committee.
