Hunter Biden’s deal with prosecutors to plead guilty to two misdemeanour tax evasion charges and defer punishment for lying on a gun license application collapsed in dramatic fashion in a Delaware federal courtroom on Wednesday.

As a room full of reporters watched, the presiding judge, Maryellen Noreika, questioned the assembled lawyers about details of the agreement, revealing that the federal team led by David Weiss, the Donald Trump-appointed US attorney in Delaware who is in charge of the Biden investigation, and Mr Biden’s lawyers, had very different views on what it contained.

Eventually, Mr Biden’s side agreed to the prosecution’s view – but that proved to be just the first stumbling block. The judge then questioned the gun deal – in which no charges would be filed if Mr Biden stayed out of legal trouble and did not attempt to purchase firearms for two years.

The agreement made Ms Noreika, rather than the justice department, the arbiter of whether Mr Biden was keeping his end of the agreement, a provision she found to be of questionable legality.

After she told the lawyers she could not decide the matter without further review, Mr Biden pleaded not guilty to the two tax charges and the judge told the sides they would have 30 days to reach a new agreement that addressed her concerns.

“You are all saying, ‘Just rubber stamp the agreement’,” Ms Noreika told the lawyers. “I’m not in a position to accept or reject it. I need to defer.”

In the meantime, there are more questions than there are answers.

At the heart of Wednesday’s dispute was exactly how much immunity from future prosecution the plea deal with give Hunter Biden. Defence attorneys said they understood that the agreement would protect their client from any future indictments by federal prosecutors over his business dealings.

Federal prosecutors disagreed, telling the judge the plea agreement only covered tax crimes and Mr Biden’s falsely claiming he was not a drug addict when he applied for a 2018 gun license.

It’s typical for defence attorneys to press for the broadest level of protection for their clients when entering plea negotiations. Prosecutors, on the other hand, tend to want to keep their options open. These details are usually hammered out well ahead of a courtroom appearance, however.

The Biden team has a particular interest in limiting the justice department’s range of future options, both in new prosecutions and determining violations of the gun agreement, to prevent a Republican president from reopening the inquiry in 2025.

In the end, the two sides agreed that Mr Biden would be protected from further tax and gun charges stemming activities that took place between 2014 and 2019.

When asked by congressional investigators, Mr Weiss and federal prosecutors have said that their investigations are “ongoing” despite the plea deal.

During their Wednesday court appearance, Judge Noreika specifically asked the prosecution team about whether the plea deal would prevent a prosecution for violation of the Foreign Agents Registration Act (Fara) – a federal law that requires individuals who are engaging in political advocacy on behalf of foreign governments, businesses or nationals to inform the federal government of their activities.

The prosecutors said it did not.

There has been widespread speculation that Mr Weiss’s team has been looking into possible Fara violations, given that Mr Biden had frequent contacts with Chinese and Ukrainian individuals and businesses as part of his international business dealings.

While the prosecutors did not confirm this as an ongoing area of investigation, the judge’s questions will further fuel speculation.

Fara prosecutions were rare until recent years and typically come through plea deals and not trials.

Former Trump campaign chair Paul Manafort pleaded guilty to a Fara charge in 2019, as did former Republican fundraiser Elliott Broidy in 2020. Both were subsequently pardoned by Mr Trump.

The clock is ticking on the 30-day deadline for prosecutors and Mr Biden’s lawyers to reach a plea agreement that won’t collapse when it reaches the courtroom.

If they can’t, the judge could set a trial date for the two misdemeanour tax violations the presidential son is already facing – and prosecutors could add more serious criminal violations to the charge sheet.

If a new deal is reached, Judge Noreika will have to approve it – and then issue a sentence. While the prosecutors had recommending parole and no jail time as part of the previous deal, the judge will make her own determination as to the appropriate punishment.

Meanwhile, congressional Republicans, who are conducting their own investigation of Mr Biden’s business activities will continue their inquiries.

They had actively opposed the previous plea agreement, which they considered too lenient for Mr Biden.

House Oversight Committee Chair James Comer has said that committee Republicans believe that President Biden may be more closely tied to Hunter Biden’s businesses than was previously disclosed.

Mr Weiss had promised to testify to Congress sometime after August to explain the plea deal and his prosecutorial decisions, but that becomes less likely if his office takes Mr Biden to trial on tax charges or is actively investigating other possible criminal violations.

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