Boris Epshteyn is the latest aide to take on the role of slashing defender of the former president, even as the Justice Department seeks information about him in the Jan. 6 and documents inquiries.Boris Epshteyn has had his phone seized by federal agents investigating former President Donald J. Trump’s efforts to remain in power after his election loss. Lacking any track record as a political strategist, he has made more than $1.1 million in the past two years for providing advice to the campaigns of Republican candidates, many of whom believed he could be a conduit to Mr. Trump.A cryptocurrency with which he is involved has drawn scrutiny from federal prosecutors. And he has twice been arrested over personal altercations, leading in one case to an agreement to attend anger management classes and in another to a guilty plea for disorderly conduct.As the former president faces escalating legal peril in the midst of another run for the White House, Mr. Epshteyn, people who deal with him say, mirrors in many ways Mr. Trump’s defining traits: combative, obsessed with loyalty, transactional, entangled in investigations and eager to make money from his position.Mr. Epshteyn is the latest aide to try to live up to Mr. Trump’s desire for a slashing defender in the mold of his first lawyer protector, Roy M. Cohn. He serves as a top adviser and self-described in-house counsel for Mr. Trump, at a time when the former president has a growing cast of outside lawyers representing him in a slew of investigations and court cases.A Trump spokesman, Steven Cheung, called Mr. Epshteyn “a deeply valued member of the team” and said he has “done a terrific job shepherding the legal efforts fighting” the Justice Department and congressional investigations.Mr. Epshteyn declined to comment for this article.Mr. Epshteyn speaks with Mr. Trump several times a day and makes it known that he does so, according to interviews with Trump associates and other Republicans. He has recommended, helped hire and negotiated pay for several lawyers working for Mr. Trump on civil litigation and the federal and local criminal investigations swirling around him.As Mr. Epshteyn has worked to establish his place as a key legal adviser to Mr. Trump, he has profited from his ties to the former president — and come under scrutiny himself.Desiree Rios/The New York Times“Boris is a pair of heavy hands — he’s not Louis Brandeis,” said Stephen K. Bannon, a close ally of Mr. Epshteyn and former adviser to Mr. Trump, referring to the renowned Supreme Court justice. But Mr. Trump, he said, “doesn’t need Louis Brandeis.”“You need to be a killer, and he’s a killer,” Mr. Bannon added.But Mr. Epshteyn’s attacking style grates on other people in Mr. Trump’s circle, and he has encouraged ideas and civil lawsuits that have frustrated some of Mr. Trump’s lawyers, like suits against the journalist Bob Woodward and the Pulitzer Prize committee. His detractors see him as more of a political operative with a law license than as a provider of valuable legal advice.“As soon as anybody starts making anything happen for Trump overall, the knives come out,” Mr. Bannon said. He described Mr. Epshteyn as “a wartime consigliere.”Federal records show that Mr. Epshteyn was paid nearly $200,000 by Mr. Trump’s political action committee over seven months in 2022, and $30,000 by his 2024 campaign. The past payments were almost all listed in Federal Election Commission records as for “strategy consulting,” not legal work.After the search last summer of Mar-a-Lago by F.B.I. agents looking for classified documents still in Mr. Trump’s possession, Mr. Epshteyn retroactively changed his agreement with the political action committee. The agreement, which had been primarily for communications strategy, was updated to include legal work, and to say it covered legal work since the spring of last year, a campaign official said. His monthly retainer doubled to $30,000.But he dropped a separate effort to have Mr. Trump sign a letter retroactively designating him as a lawyer for Mr. Trump personally, dating to March of last year, soon after Mr. Trump’s post-presidency handling of classified documents became an issue. The letter specifically stated that their communications would be covered by attorney-client privilege, multiple people familiar with the request said.The Justice Department has recently sought to pierce assertions of attorney-client privilege by another of Mr. Trump’s lawyers, M. Evan Corcoran, and compel him to answer more questions before a grand jury in the special counsel’s investigation into the former president’s handling of classified documents.But even as Mr. Epshteyn has worked to establish his place as a key legal adviser to Mr. Trump, he has also profited from his ties to the former president and his supporters as a strategist and political adviser.Prosecutors have sought information related to Mr. Epshteyn in investigations into Mr. Trump’s efforts to thwart the transfer of power. They have also asked about Mr. Epshteyn’s role connecting two attorneys to respond to the Justice Department inquiry into classified material. Hailey Sadler for The New York TimesFederal records show the only candidates who paid Mr. Epshteyn for work before 2020 were the Republican senator John McCain, for his 2008 presidential race, and Mr. Trump. But in the 2022 midterm election cycle, he had contracts with at least 13 candidates, some of them interested in having Mr. Trump’s support, or in preventing attacks from him or other MAGA figures with whom Mr. Epshteyn has close connections.Bernard B. Kerik, a close Epshteyn ally who worked with him on a few races, said Mr. Epshteyn has an expansive list of contacts and offered advice on polling and social media. Some Republicans said he provided help with opinion essays and fund-raising targets. But some campaigns that paid his monthly retainers said they were skeptical of his value..css-1v2n82w{max-width:600px;width:calc(100% – 40px);margin-top:20px;margin-bottom:25px;height:auto;margin-left:auto;margin-right:auto;font-family:nyt-franklin;color:var(–color-content-secondary,#363636);}@media only screen and (max-width:480px){.css-1v2n82w{margin-left:20px;margin-right:20px;}}@media only screen and (min-width:1024px){.css-1v2n82w{width:600px;}}.css-161d8zr{width:40px;margin-bottom:18px;text-align:left;margin-left:0;color:var(–color-content-primary,#121212);border:1px solid var(–color-content-primary,#121212);}@media only screen and (max-width:480px){.css-161d8zr{width:30px;margin-bottom:15px;}}.css-tjtq43{line-height:25px;}@media only screen and (max-width:480px){.css-tjtq43{line-height:24px;}}.css-x1k33h{font-family:nyt-cheltenham;font-size:19px;font-weight:700;line-height:25px;}.css-1hvpcve{font-size:17px;font-weight:300;line-height:25px;}.css-1hvpcve em{font-style:italic;}.css-1hvpcve strong{font-weight:bold;}.css-1hvpcve a{font-weight:500;color:var(–color-content-secondary,#363636);}.css-1c013uz{margin-top:18px;margin-bottom:22px;}@media only screen and (max-width:480px){.css-1c013uz{font-size:14px;margin-top:15px;margin-bottom:20px;}}.css-1c013uz a{color:var(–color-signal-editorial,#326891);-webkit-text-decoration:underline;text-decoration:underline;font-weight:500;font-size:16px;}@media only screen and (max-width:480px){.css-1c013uz a{font-size:13px;}}.css-1c013uz a:hover{-webkit-text-decoration:none;text-decoration:none;}How Times reporters cover politics. We rely on our journalists to be independent observers. So while Times staff members may vote, they are not allowed to endorse or campaign for candidates or political causes. This includes participating in marches or rallies in support of a movement or giving money to, or raising money for, any political candidate or election cause.Learn more about our process.“It’s a mystery; we’re still trying to figure it out,” said Carl Paladino, a Republican who failed in his primary race in a congressional district in Western New York last year, when asked what Mr. Epshteyn did for $20,000 on what was a three-month House primary campaign.“He was highly recommended as having good relations with some people that work for Trump,” said Mr. Paladino, who did not receive Mr. Trump’s endorsement. He added: “I was told that it would be in my interest if I sent money to this Boris. I did, and we heard nothing from the man. He was totally useless.”Some former aides to Mr. Paladino said that the candidate was livid over his loss and that Mr. Epshteyn had in fact provided advice and assistance to senior aides.An adviser to another candidate seeking a Trump endorsement, who was not authorized to speak publicly, said the candidate’s team had hoped Mr. Epshteyn would praise the candidate to Mr. Trump or at least help avoid public criticism from him. Advisers to Mr. Trump have long said Mr. Epshteyn often tries to influence the former president’s views.Several people involved with campaigns that hired Mr. Epshteyn said he had made it clear that he could not promise an endorsement from Mr. Trump. But some said Mr. Epshteyn described himself as someone who understood Mr. Trump’s hard-core base. Some campaigns, one Republican operative said, saw him as an effective way to get information about what was happening within Mr. Trump’s orbit.Mr. Epshteyn was paid $95,000 over four months by Senator Katie Britt’s campaign in Alabama. Another $82,500 came from Eric Greitens’s losing Senate campaign in Missouri. Over three months, he was paid $60,000 by the losing Don Bolduc Senate campaign in New Hampshire.Representative Eli Crane’s campaign in Arizona paid him $125,000. The cryptocurrency entrepreneur Brock Pierce in Vermont paid him $100,000, but ultimately did not run for a Senate seat.Mr. Epshteyn’s legal role with Mr. Trump, while less often focused on gritty legal details, has been to try to serve as a gatekeeper between the lawyers on the front lines and the former president, who is said to sometimes roll his eyes at the frequency of Mr. Epshteyn’s calls but picks up the phone.“Boris has access to information and a network that is useful to us,” said one of the team’s lawyers, Timothy Parlatore, whom Mr. Epshteyn hired. “It’s good to have someone who’s a lawyer who is also inside the palace gates.”Mr. Parlatore suggested that he was not worried that Mr. Epshteyn, like a substantial number of other Trump lawyers, had become at least tangentially embroiled in some of the same investigations on which he was helping to defend Mr. Trump.“Absent any solid indication that Boris is a target here, I don’t think it affects us,” Mr. Parlatore said.“Going after the lawyers is a tactic D.O.J. uses to wear you down and remove your defenses,” he added, referring to the Justice Department. “And it’s dirty.”Prosecutors have sought information related to Mr. Epshteyn in investigations into Mr. Trump’s efforts to thwart the transfer of power. Of particular interest are his work with Rudolph W. Giuliani and his alleged involvement in securing so-called alternate electors in an attempt to overturn Mr. Trump’s loss in the 2020 presidential election, people familiar with the matter said. Mr. Epshteyn also testified before a fact-finding grand jury in Fulton County, Ga., looking into efforts to overturn Mr. Trump’s election loss in that state.Prosecutors investigating Mr. Trump’s handling of classified material have looked at whether Mr. Epshteyn improperly sought a common-interest agreement among witnesses as a shield against the investigation, the people familiar with the matter said.Prosecutors have also asked about his role connecting two attorneys to respond to the Justice Department inquiry into classified material. The two lawyers then produced a statement in June saying that to the best of their knowledge all of the classified documents being kept at Mar-a-Lago had been returned to the government in compliance with a subpoena — which turned out to be untrue.More recently, a pro-Trump cryptocurrency that Mr. Epshteyn and Mr. Bannon are involved with managing is facing an inquiry from federal prosecutors in the Southern District of New York, according to a person familiar with the matter. ABC News reported that the management of the cryptocurrency has been criticized, including for not fulfilling charitable pledges.Mr. Epshteyn, whose family emigrated from the Soviet Union when he was young and who grew up in New Jersey, attended Georgetown University with Mr. Trump’s son, Eric, and then Georgetown’s law school. He worked at the firm Milbank Tweed for nearly three years.He became a television surrogate on the 2016 Trump campaign, hired late in the race.“He desperately wanted to be part of the inner circle,” said Michael D. Cohen, Mr. Trump’s former lawyer and fixer who is now a key witness against Mr. Trump.Mr. Epshteyn, left, speaking at Trump Tower in 2016. He became a television surrogate on the 2016 Trump campaign and also joined Mr. Trump’s 2020 campaign.Hilary Swift for The New York TimesMr. Epshteyn worked on the presidential inaugural committee after Mr. Trump’s victory, and then briefly in the White House, leaving after an issue arose with his security clearance. (A person briefed on the matter said the issue has been resolved.)He was the chief political analyst for Sinclair Broadcast Group until December 2019. After losing his on-air role, Mr. Epshteyn remained a consultant with Sinclair. He was hired months later by the 2020 Trump campaign as a strategic adviser.He has faced other legal entanglements over the years.Mr. Epshteyn was arrested in Arizona in 2014 for an alleged assault in a bar; the charges were dropped when he agreed to anger management classes.In October 2021, he was arrested in Arizona again after a woman claimed he had inappropriately touched her and a friend, telling the police he appeared as a less attractive “version of Tony Soprano,” according to a copy of the police report. Mr. Epshteyn denied the claims to the police. Prosecutors dropped charges related to sexual misconduct; Mr. Epshteyn pleaded guilty to disorderly conduct. He was ordered to attend an alcohol abuse prevention program and put on probation, which ended last year. The conviction was set aside last year.Several people who have worked closely with Mr. Epshteyn compared his impulse to please Mr. Trump to that of Mr. Cohen, a comparison disputed by supporters of Mr. Epshteyn but backed by Mr. Cohen.“He’s a great mimic,” Mr. Cohen said. “He watched me with hungry eyes in terms of how to maneuver around Trump.”Ben Protess More