The dismissal of charges against Hunter Biden at Delaware in the wake of his failed “sweetheart plea deal” makes it very likely that Mr. Biden will be tried on criminal tax evasion and firearms offenses in California or at the District of Columbia. Based on a previous threat by Mr. Biden’s attorneys, could the star witness in the first son’s trial be President Biden?

On August 18, the judge who delayed Mr. Biden’s plea deal, Maryellen Noreika, dismissed the charges against the first son, which were the basis for his plea agreement. The United States attorney for Delaware, David Weiss, who now also serves as a special counsel for the Department of Justice, said that “the Government now believes that the case will not resolve short of a trial.”

Mr. Weiss, who allegedly sought to bring charges against Mr. Biden in both the first son’s former and current home districts — the District of Columbia and the Central District of California — is now likely to initiate a prosecution that could involve the president himself.

On August 19, Politico’s Betsy Woodruff Swan disclosed the existence of a 32-page letter that Mr. Biden’s attorney, Christopher Clark, had sent to Mr. Weiss in 2022. Should Mr. Weiss bring charges against the first son, Mr. Clark wrote, “President Biden now unquestionably would be a fact witness for the defense in any criminal trial.”

“This of all cases justifies neither the spectacle of a sitting President testifying at a criminal trial nor the potential for a resulting Constitutional crisis,” Mr. Clark wrote.

The elder Mr. Biden has long defended his son in public against charges that he had done anything wrong in his foreign business dealings and has denied allegations that he was in any way involved. Should the first son be charged at either the nation’s capital or in California, the president could be called as a personal witness for his son. Mr. Biden has long framed his son’s legal troubles as a result of his addiction to drugs and alcohol rather than alleged violations of federal law. 

Over the past five years, the elder Mr. Biden has played a key role, as a father, in his son’s recovery from drug and alcohol addiction. He also, despite repeated denials, had contact with his son’s business partners, calling into meetings with his son’s foreign clients and having dinner with them as the first son effectively sold access, real or imagined, to his father, according to allegations from the younger Mr. Biden’s former friend and business partner, Devon Archer. 

After the collapse of the plea deal he helped negotiate, Mr. Clark withdrew as Mr. Biden’s attorney because he believed he would be called as a witness in any forthcoming prosecution. Mr. Clark did not immediately respond to a request for comment. 

At Delaware, the younger Mr. Biden attempted to plead guilty to two misdemeanor counts of “willful” tax evasion, which would have allowed him to avoid prison time. Judge Noreika asked whether he was immune from future prosecutions, which the lawyers were unable to answer due to divergent interpretations of the agreement. 

Beyond the tax charges, the first son was also seeking to enter a pretrial diversion program for his illegal purchase of a firearm, the penalty for which can be a stiff prison term under legislation the elder Mr. Biden supported while in the Senate. The violation took place at Delaware at the height of Hunter Biden’s addiction, which could lead to another prosecution at his home state, led by Mr. Weiss’s office. 

The younger Mr. Biden could also face charges of violating the Foreign Agents Registration Act, the prospect of which was explicitly raised by Judge Noreika during the plea agreement hearing in July. “There are references to foreign companies, for example, in the facts section,” Judge Noreika said, referring to the plea agreement that disclosed some of the foreign lobbying Mr. Biden allegedly did on behalf of business interests. “Could the government bring a charge under the Foreign Agents Registration Act?” she asked. 

As the former vice president was a key player in his son’s work with foreign clients, especially in Ukraine, he would be a likely witness in any prosecution of the younger Mr. Biden for FARA violations.

According to Politico, Mr. Clark warned Mr. Weiss that if the elder Mr. Biden were called to the stand in his son’s defense, it could precipitate a “constitutional crisis,” with the president effectively testifying against his own Department of Justice. 

The likelihood of a prosecution of the first son by the executive branch is compounded by the public relations battle the first son is currently having with the legislative branch. 

The chairman of the House Oversight Committee, Congressman James Comer, has said the impeachment of the elder Mr. Biden has grown increasingly likely amid the slew of information made public by his committee, including documents that show millions of dollars were transferred to members of the president’s family from overseas business interests and the disclosure that the elder Mr. Biden joined at least 20 of his son’s meetings via telephone.