Did former President Donald J. Trump consume detailed information about foreign countries while in office? How extensively did he seek information about whether voting machines had been tampered with? Did he indicate he knew he was leaving when his term ended?
Those are among the questions that Justice Department investigators have been directing at witnesses as the special counsel, Jack Smith, takes control of the federal investigations into Mr. Trump’s efforts to reverse his 2020 election loss and his handling of classified documents found in his possession after he left office.
Through witness interviews, subpoenas and other steps, Mr. Smith has been moving aggressively since being named to take over the inquiries nearly three months ago, seeking to make good on his goal of resolving as quickly as possible whether Mr. Trump, still a leading contender for the 2024 Republican presidential nomination, should face charges.
Last week, he issued a subpoena to former Vice President Mike Pence, a potentially vital witness to Mr. Trump’s actions and state of mind in the days before the Jan. 6, 2021, assault on the Capitol by a pro-Trump mob.
His prosecutors have brought a member of Mr. Trump’s legal team, M. Evan Corcoran, before a federal grand jury investigating why Mr. Trump did not return classified information kept at his Mar-a-Lago residence and private club in Florida. Justice Department officials have interviewed at least one other Trump lawyer in connection with the documents case.
Since returning to Washington from The Hague, where he had been a war crimes prosecutor, Mr. Smith has set up shop across town from the Justice Department’s headquarters, and has built out a team. His operation’s structure seems to closely resemble the organization he oversaw when he ran the Justice Department’s public integrity unit from 2010 to 2015.
Three of his first hires — J.P. Cooney, Raymond Hulser and David Harbach — were trusted colleagues during Mr. Smith’s earlier stints in the department. Thomas E. Windom, a former federal prosecutor in Maryland who had been tapped in late 2021 by Attorney General Merrick B. Garland to oversee major elements of the Jan. 6 inquiry, remains part of the leadership team, according to several people familiar with the situation.
In addition to the documents and Jan. 6 investigations, Mr. Smith appears to be pursuing an offshoot of the Jan. 6 case, examining Save America, a pro-Trump political action committee, through which Mr. Trump raised millions of dollars with his false claims of election fraud. That investigation includes looking into how and why the committee’s vendors were paid.
Interviews with current and former officials, lawyers and other people who have insight into Mr. Smith’s actions and thinking provide an early portrait of how he is managing investigations that are as sprawling as they are politically explosive, with much at stake for Mr. Trump and the Justice Department.
Current and former officials say Mr. Smith appears to see the various strands of his investigations as being of a single piece, with interconnected elements, players and themes — even if they produce divergent outcomes.
Mr. Smith has kept a low profile, making no public appearances and sticking to a long pattern of empowering subordinates rather than interposing himself directly in investigations. It is a chain-of-command style honed during stints as a war crimes prosecutor in The Hague, a federal prosecutor in Tennessee and, most of all, during his tenure running the Justice Department’s public integrity unit, which investigates elected officials.
A spokesman for the Mr. Smith had no comment.
But various developments that have surfaced publicly in recent days show his team taking steps on multiple fronts, illustrating how he is wrestling with multiple and sometimes conflicting imperatives of conducting an exhaustive investigation on a strictly circumscribed timetable.
The intensified pace of activity speaks to his goal of finishing up before the 2024 campaign gets going in earnest, probably by summer. At the same time, the sheer scale and complexity and the topics he is focused on — and the potential for the legal process to drag on, for example in a likely battle over whether any testimony by Mr. Pence would be subject to executive privilege — suggest that coming to firm conclusions within a matter of months could be a stretch.
“The impulse to thoroughly investigate Trump’s possibly illegal actions and the impulse to complete the investigation as soon as possible, because of presidential election season, are at war with one another,” said Jack Goldsmith, a former assistant attorney general and current Harvard Law professor. “One impulse will likely have to yield to the other.”
In looking into Mr. Trump’s efforts to hold onto power after his election loss and how they led to the Jan. 6 riot, Mr. Smith is overseeing a number of investigative strands. The subpoena to Mr. Pence indicates that he is seeking testimony that would go straight to the question of Mr. Trump’s role in trying to prevent certification of Joseph R. Biden Jr.’s victory in the election and the steps Mr. Trump took in drawing a crowd of supporters to Washington and inciting them.
His team is sifting through mountains of testimony provided by the House Jan. 6 committee, including focusing on the so-called fake electors scheme in which some of Mr. Trump’s advisers and some campaign officials assembled alternate slates of Trump electors from contested states that he had lost.
More recently his team has been asking witnesses about research the Trump campaign commissioned by an outside vendor shortly after the election that was intended to come up with evidence of election fraud. The existence of that research was reported earlier by The Washington Post.
The apparently related investigation into the activities of Mr. Trump’s main fund-raising arm, the Save America PAC in Florida, was emerging even before Mr. Smith arrived in Washington around Christmas from The Hague.
A vast array of Trump vendors have been subpoenaed. Investigators have been posing questions related to how money was paid to other vendors, indicating that they are interested in whether some entities were used to mask who was being paid or if the payments were for genuine services rendered.
In the investigation into Mr. Trump’s handling of classified information, and whether he obstructed justice when the government sought the return of material he had taken from the White House, investigators are casting a wide net. They appear to be seeking to recreate not only what took place once Mr. Trump had departed the White House with hundreds of sensitive documents, but also how he approached classified material and presidential records long before that, according to multiple people briefed on the matter.
Mr. Smith’s team is seeking interviews with a number of people who worked in the Trump White House and who had familiarity with either how he consumed classified information, or how he dealt with paper that he routinely carted with him in cardboard boxes, during much of the span of his presidency.
Such interviews could help Mr. Smith establish patterns of behavior by Mr. Trump over time, such as how he handled secret information he was provided about foreign countries and how he treated presidential documents generally.
Mr. Trump was known to rip up pieces of paper, and to bring documents up to the White House residence. Notes taken by aides in 2018 show that Mr. Trump’s advisers appeared to be contending with tracking documents he had brought with him to his club in Bedminster, N.J., where he stayed over weekends during the warmer months of the year.
In some cases, Mr. Trump tore up documents and threw them in toilets in the White House. Aides would periodically retrieve what was not flushed down and let it dry, then tape it back together and pass the documents on to the staff secretary, whose office managed presidential paper flow, according to two people familiar with what took place.
In the documents investigation, Mr. Smith has the challenge of interviewing several unreliable narrators who may have an interest in protecting Mr. Trump.
Several of Mr. Trump’s advisers have been interviewed by the Justice Department. Some have gone before the grand jury, including Mr. Corcoran, who has represented Mr. Trump in the case related to his handling of classified material for many months and had a central role in dealing with the government’s efforts to retrieve the documents, according to two people briefed on his appearance.
Another aide to Mr. Trump, Christina Bobb, served as the custodian of the records the Justice Department was interested in. She signed an attestation in June claiming that a “diligent search” had been conducted of Mar-a-Lago in response to a grand jury subpoena. She asserted that the remaining documents turned over in June were all that remained.
Ms. Bobb has appeared twice before the Justice Department and has told people that Mr. Corcoran drafted the statement she signed; The Wall Street Journal reported that one visit was before the grand jury. She has also said she was connected with Mr. Corcoran by Boris Epshteyn, another Trump lawyer and adviser who brought Mr. Corcoran into Mr. Trump’s circle and, empowered by Mr. Trump, for months played a lead role coordinating lawyers in some of the investigations.
The Justice Department contacted another of Mr. Trump’s lawyers, Alina Habba, late last year about an appearance. Ms. Habba does not represent Mr. Trump in the documents case, but she spoke about it on television. She also signed an affidavit in another case saying she had searched Mr. Trump’s office and residence in May, meaning investigators may be interested in whether she saw government documents there.
The Justice Department is also seeking to question a former Trump lawyer, Alex Cannon, who people briefed on the matter said repeatedly urged Mr. Trump to turn over the boxes of material that the National Archives was seeking.
Mr. Trump’s disclosure of newly located documents has been ongoing. Lawyers for the former president notified prosecutors recently about a potential witness they might want to speak with: a relatively junior former staff member to Mr. Trump who had uploaded classified material onto a laptop and discovered it only after the fact, according to a different person familiar with the incident.
The discovery occurred when the staff member was placing a large trove of Mr. Trump’s daily White House schedules on the computer and realized that a small amount of classified material had been included in the schedules, the person said.
“I’ve never seen anything like it,” Chuck Rosenberg, a former federal prosecutor and former F.B.I. official, said of the cascade of Trump aides and lawyers becoming drawn into investigations. “It’s just a whirling dust cloud, and everyone who gets near it gets covered in grime.”
While Mr. Smith did not ask Mr. Garland’s permission to subpoena Mr. Pence, one of the most extraordinary developments of his short time as special counsel, he almost certainly consulted him about it: Under the regulations, special counsels are expected to report major developments to the attorney general.
But many legal observers see the current situation — with two likely 2024 presidential rivals, Mr. Trump and Mr. Biden, facing separate special counsel investigations — as evidence that the special counsel mechanism is being used far beyond its intended, limited purpose.
“The special counsel regulations were an effort to give the attorney general some independence in a conflict-of-interest situation,” Mr. Goldsmith added, “but it was never intended to carry the burdens that are being imposed on it now. It is a problem, these political investigations, that our constitutional system is not equipped to handle.”
Ben Protess contributed reporting.
