U.S. Attorney Investigating Hunter Biden Is Made a Special Counsel

Mr. Garland said he decided to elevate Mr. Weiss after the prosecutor informed him on Tuesday the investigation had “reached the stage” where the powers of a special counsel were necessary to continue. Mr. Weiss would have the authority to investigate all related matters in his inquiry and could bring charges in any jurisdiction, Mr. Garland added, meaning that Mr. Weiss would not be subject to day-to-day supervision by any official at the department.

He described Mr. Weiss, who was appointed by former President Donald J. Trump and kept on by Mr. Garland to complete the investigation, as a “career prosecutor.”

“The appointment of Mr. Weiss reinforces for the American people the department’s commitment to both independence and accountability in particularly sensitive matters,” Mr. Garland said. “I am confident that Mr. Weiss will carry out his responsibility in an evenhanded and urgent manner and in accordance with the highest traditions of this department.”

Mr. Garland did not take any questions.

The appointment on Friday all but ensures that a yearslong investigation into a wide array of conduct in Hunter Biden’s life — including his foreign business dealings, drug use and taxes — will continue on even longer. The investigation appeared to be coming to an end weeks ago, but in an unexpected move, a federal judge in Delaware refused to approve a proposed plea deal that would have settled tax and gun charges.

The decision is likely to anger the president and Democrats. They have privately complained about the attorney general, who they believe moved too slowly to investigate former Mr. Trump’s attempts to overturn the 2020 election and should not have appointed a different special counsel, Robert K. Hur, to investigate whether President Biden has mishandled classified documents.

Mr. Biden’s lawyer, Christopher Clark, said he expected “a fair resolution” to the case whether it is charged in Delaware, Washington or elsewhere.

“This U.S. attorney has diligently been investigating my client for five years, and he had proposed a resolution which we fully intend to pursue in court,” Mr. Clark said in a statement. “It is hard to see why he would have proposed such a resolution if there were other offenses he could have successfully prosecuted, and we are aware of none.”

In June, Mr. Weiss and Mr. Clark signaled that they had reached a plea deal that suggested the investigation would end. Around that time, House Republicans brought forth two I.R.S. agents who worked on the investigation and claimed that there had been political interference.

Late last month, a federal judge in Wilmington, Del., put the plea deal on hold, expressing a range of concerns. Mr. Clark and the Justice Department prosecutors overseeing the case had distinctly different understandings of the immunity Hunter Biden had received from the deal and the judge had a range of concerns about it.

Judge Maryellen Noreika of the Federal District Court in Wilmington, Del., asked the two sides to work out modifications that would address her concerns and salvage the basic contours of the agreement.

The move comes seven months after Mr. Garland appointed Mr. Hur to investigate Mr. Biden’s handling of classified documents.

The announcement means that while Mr. Trump, who is leading the Republican primary, will be dogged by three — possibly four — criminal cases as he runs for president, Mr. Biden’s supporters will have to worry about both the special counsel investigation into classified documents and whether the case against his son will become more serious.

House Republicans quickly signaled the special counsel appointment would not alleviate their criticism of the investigation into Hunter Biden.

“This is just a new way to whitewash the Biden family’s corruption,” said Russell Dye, a spokesman for Representative Jim Jordan, Republican of Ohio and the chairman of the Judiciary Committee. “Weiss has already signed off on a sweetheart plea deal that was so awful and unfair that a federal judge rejected it.”

Since the announcement of the plea deal, Republicans in Congress have sharply criticized the government, accusing the Justice Department of cutting a “sweetheart deal” with the president’s son as they conduct their own investigation in an effort to tie his overseas business dealings to Mr. Biden. They have interviewed Hunter Biden’s former business partner and published summaries of WhatsApp messages and unproven allegations from an informant. They have accused the Justice Department of failing to follow tips that could lead to the president and demanded an accounting of specific steps the agency took — or did not take — in the investigation.

The two I.R.S. investigators testified before Congress against the Justice Department over its handling of the case, describing how they believed their work was stymied and delayed during the Trump and Biden presidencies.

One allegation made by the I.R.S. agents was that Mr. Weiss had sought to bring charges against Hunter Biden in Washington and California but was rebuffed after prosecutors in those jurisdictions declined to partner with him. Mr. Weiss has maintained he can obtain special attorney status to bring cases in states outside of Delaware should he make such a request of Mr. Garland.

House Republicans have also issued subpoenas to six banks, detailing millions that were paid to Hunter Biden and his business partners from overseas companies. They also interviewed a former business partner who offered an unflattering portrait of Mr. Biden’s actions.

The business partner, Devon Archer, also suggested questionable judgment on the part of President Biden, who, while vice president, repeatedly allowed himself to be in the presence — either physically or by phone — of business associates of his son’s who were apparently seeking connections and influence in government, according to Mr. Archer’s testimony.

Even so, Mr. Archer said he knew of no wrongdoing by the president.

Mr. Archer has already testified before the Delaware grand jury investigating the case and was granted immunity as part of that investigation, his lawyer said.

Chris Cameron contributed reporting.