Eventually, the Justice Department obtained a grand jury subpoena for documents with classification markings remaining in Mr. Trump’s possession, and a lawyer for Mr. Trump turned over several more and told the department there were none left. But an August search by the F.B.I. found 103 more marked as classified — along with thousands of other official records.
The search warrant affidavit that the Justice Department submitted suggested that Mr. Trump was under investigation for obstruction, along with possible violations of the Espionage Act, which criminalizes the willful retention of national security documents and failure “to deliver them on demand” to a government official entitled to take custody of them.
Still, whatever the legal questions, as a matter of political reality, the discovery will make the optics of the Justice Department potentially charging Mr. Trump over his handling of the documents more difficult. Attorney General Merrick B. Garland has assigned that investigation, along with one into Mr. Trump’s efforts to overturn the 2020 election results and the Jan. 6 attack on Congress, to Jack Smith, serving as a special counsel.
Mr. Lausch, one of two U.S. attorneys held over from the Trump administration, has been reviewing the matter since early November, according to a person familiar with the situation.
The department’s leadership decided to make the unusual choice of assigning the case outside the jurisdictions involved because Mr. Lausch was a Republican appointee and his work would be likely to be seen as impartial, the person said.
Mr. Lausch was kept in office at the request of the two Democratic senators from Illinois, Richard J. Durbin and Tammy Duckworth, because he was investigating Michael J. Madigan, the former speaker of the Illinois House of Representatives, during the presidential transition in 2021. In March, a federal grand jury indicted Mr. Madigan, a Democrat, on 22 counts of racketeering and corruption charges.
A department spokesman had no comment on the matter, and would not say whether the national security division, which has spearheaded the investigation into Mr. Trump’s retention of documents at his Florida residence and resort, was also involved.
With Mr. Lausch investigating Mr. Biden’s handling of classified information, and David Weiss, the U.S. attorney in Delaware, investigating the president’s son, Hunter Biden, both Trump U.S. attorneys who have remained at the department are now investigating the Biden family.
Katie Benner contributed reporting.