Hunter Biden, the president’s son, was charged on Thursday by federal prosecutors with lying about his drug use in connection with his purchase of a handgun in 2018, a move that could put him on trial next year as his father runs for re-election.
The decision to file criminal charges against President Biden’s troubled youngest son was an extraordinary step for the Justice Department and the lead prosecutor on the case, David C. Weiss, whom Attorney General Merrick B. Garland named as a special counsel last month. Mr. Garland gave Mr. Weiss that status after the last-minute collapse of a previous deal that would have resolved the long-running investigation without Mr. Biden serving prison time.
The collapsed deal also would have resolved an investigation into Mr. Biden’s late filings of his tax returns for several years. Prosecutors did not file tax charges against Mr. Biden on Thursday but could still do so. Mr. Weiss’s team has also signaled that it continues to investigate other elements of Mr. Biden’s business activities, most likely including whether any of his work with foreign interests violated the Foreign Agents Registration Act, which requires disclosure of lobbying activities for other countries.
The three counts lodged by prosecutors in the gun case were related to whether Mr. Biden had lied on a federal government form that he was required to complete when he purchased a handgun in Delaware in 2018. In response to a question on the form about whether he was using drugs, Mr. Biden had said he was not — an assertion that prosecutors concluded was inaccurate.
The indictment comes as House Republicans are stepping up their efforts to use Hunter Biden’s work abroad to build a case for impeaching his father. And it puts the Biden Justice Department in the remarkable position of prosecuting cases against both the president’s son and former President Donald J. Trump, the current front-runner for the Republican Party’s 2024 presidential nomination.
Mr. Trump has been charged in separate federal cases with seeking to overturn his loss in the 2020 election and with mishandling classified documents after leaving office and obstructing efforts to retrieve them.
President Biden was vice president during part of the period when his son was serving on the board of Burisma, a Ukrainian energy firm, and pursuing investment deals in China, ventures that yielded Hunter Biden millions of dollars in income.
The gun charge, which carries a maximum sentence of 10 years, is only sporadically brought against first-time offenders, particularly ones like Mr. Biden, who is not accused of using the weapon in another crime.
Mr. Biden’s lawyers have argued to Justice Department officials that the charge will ultimately be thrown out because a series of Supreme Court and appeals court decisions have cast doubt on the constitutionality of the federal government putting certain conditions on firearms purchases.
Mr. Weiss had also been investigating Mr. Biden’s failure to file his 2017 and 2018 tax returns on time. Under the plea deal that collapsed this summer, Mr. Biden would have pleaded guilty to two misdemeanor counts stemming from the tax investigation.
Mr. Weiss, who is the U.S. attorney for Delaware and was appointed to that post by Mr. Trump, filed the gun charges in Delaware, where the handgun purchase took place. Should he file tax charges, his status as special counsel would allow him to do so in other jurisdictions where Mr. Biden was living during the period when he failed to file on time, including California and Washington, D.C.
The investigation of Mr. Biden appeared to have come to a conclusion this summer, when his lawyers and Mr. Weiss announced a plea deal and a hearing was scheduled at the federal courthouse in Delaware.
Mr. Biden was to plead guilty to two misdemeanor tax charges under that agreement. In regards to the gun purchase, prosecutors agreed not to prosecute him on the charge under a so-called pretrial diversion agreement, which would have required Mr. Biden to admit that he was using drugs at the time of the purchase. The deal was contingent on him remaining drug free for the next two years.
But at the plea hearing in federal court in July, the deal unraveled. There was a major disagreement between Mr. Weiss’s prosecutors and Mr. Biden’s lawyer, Christopher J. Clark, about whether the deal included an immunity clause that insulated him from being prosecuted in connection with his foreign business dealings.
Judge Maryellen Noreika of the Federal District Court in Wilmington sharply questioned element of the deal’s structure, telling the two sides repeatedly that she had no intention of being “a rubber stamp.”
Her objections centered on two elements of the proposed deal. One was a provision that would have offered Mr. Biden broad insulation against further prosecution on matters scrutinized by federal prosecutors during the five-year inquiry. The other had to do with the diversion program on the gun charge, under which she would be called on to play a role in determining whether Mr. Biden was meeting the terms of the deal.
Judge Noreika said she was not trying to sink the agreement, but to strengthen it by ironing out ambiguities and inconsistencies. But by the end of the tumultuous hearing, the sides had splintered, prosecutors filed paperwork indicating they would proceed with a prosecution, and the embattled Mr. Weiss requested to be named special counsel, which requires him to file a report at the conclusion of the investigation.
The Hunter Biden investigation has become a central focus of House Republicans and Mr. Trump, who has seized upon it as a counter to his own legal woes. Speaker Kevin McCarthy said on Tuesday that the House would proceed with a formal impeachment investigation focused on whether President Biden and his family benefited from what Republicans have contended were corrupt activities by Hunter Biden. No evidence has surfaced publicly implicating the president in any wrongdoing.
The Justice Department has been investigating Hunter Biden since 2018. Despite looking into an array of matters — including his work for Burisma, his ties to oligarchs and his business deals in China — the investigation ultimately narrowed to the questions about Mr. Biden’s taxes and the gun purchase.
Those charges, while serious, were far less explosive than ones pushed by Mr. Trump and congressional Republicans, who have been angry with the Justice Department for failing to find wider criminal wrongdoing by the president’s son and family.