“I’m no fan of Donald Trump,” said Dan Cogdell, a Houston defense lawyer who tangled with Mr. Weissmann when Mr. Weissmann helped lead the federal task force investigating Enron in the early 2000s. “Frankly, I can’t think of two people who deserve each other more than Andrew Weissmann and Donald Trump.”
If Mr. Mueller is the stern-eyed public face of the investigation, Mr. Weissmann, 59, is its pounding heart, a bookish, legal pit bull with two Ivy League degrees, a weakness for gin martinis and classical music and a list of past enemies that includes professional killers and white-collar criminals.
Empowered by Mr. Mueller, for whom he previously worked as general counsel at the F.B.I., Mr. Weissmann has taken the lead in the government’s case against Paul Manafort, Mr. Trump’s former campaign chairman, whose indictment jolted the capital on Monday in a clear signal of the team’s seriousness.
Mr. Weissmann could be seen at an initial hearing in Washington with an easy smile, chatting up Mr. Manafort’s lawyer during a break in the action.
Friends describe Mr. Weissmann as relentless and boundary-grazing but fundamentally fair, a creative legal strategist whose hyperdiligence should not be confused with recklessness.
He is the prosecutor they would want if their relatives were charged with crimes they did not commit, they say, and the one they would dread if their family members were guilty.
“If there’s something to find, he’ll find it,” said Katya Jestin, a former colleague in the United States attorney’s office for the Eastern District of New York, who called Mr. Weissmann’s ethics unimpeachable. “If there’s nothing there, he’s not going to cook something up.”
But many defense lawyers have chafed at what they see as a scorched-earth approach, forged in Brooklyn while facing down Mafia members and refined on the government’s unit of Enron superprosecutors, which left a mixed legacy of high-profile successes, overturned convictions and one unanimous defeat at the Supreme Court.
It was Mr. Weissmann and his team who stunned Houston society by charging the wife of Enron’s chief financial officer with tax fraud, applying pressure on the executive, who became a star witness.
It was Mr. Weissmann, more recently, who oversaw the predawn raid of Mr. Manafort’s Virginia residence in July, when federal agents picked his lock and prosecutors communicated their intention to indict him.
When that moment came this week, representatives for Mr. Manafort and his longtime associate Rick Gates were given little warning: Prosecutors bypassed the common Justice Department practice of inviting lawyers to meet and discuss potential indictments beforehand, often an opportunity for the defense to argue for leniency and for prosecutors to identify potential holes in their case. As of Friday, people close to both men said they had received no indication that an indictment was imminent.
And while Mr. Mueller has remained the chief villain in the eyes of the president’s allies in conservative news media, efforts to discredit Mr. Weissmann have picked up. For months, Mr. Trump’s defenders have sought to draw attention to thousands of dollars in past donations from Mr. Weissmann to Democrats, including former President Barack Obama.
Then came the shock-and-awe raid of Mr. Manafort’s home — a Weissmann special, both admirers and critics recognized — the Zorro “Z” to announce his presence in the case.
“There’s a name,” the conservative radio host Rush Limbaugh warned listeners last week, recapping the “intimidating technique” afoot. “Weissmann.”
Working With Sammy the Bull
Prosecution can make strange bedfellows. And still this alliance stood out.
On one end of the negotiating table sat Mr. Weissmann, the Princeton-educated son of a psychologist and a research scientist who is credited with codiscovering, and coining the term, liposomes.
On the other was Salvatore Gravano, a hitman-turned-informant better known as Sammy the Bull.
Mr. Weissmann and his team used Mr. Gravano as an explosive ally in their bid to prosecute high-ranking mobsters.
Perhaps most memorably, Mr. Weissmann and his colleagues leaned on Mr. Gravano’s testimony, in large part, to dismantle Mr. Gigante’s long-held insanity defense. Mr. Gigante, nicknamed “The Oddfather,” had been known to wander Greenwich Village in a bathrobe and pajamas, mumbling incoherently, tending to a feigned image of incompetence and cluelessness. “I’ve invested many years in this crazy act,” Mr. Gravano quoted Mr. Gigante as saying during court proceedings.
Mr. Weissmann, who declined to be interviewed for this article, even demonstrated that Mr. Gigante’s bathrobes were chosen with care: In public, his coverings were soiled and tattered. Inside, he slipped into something pristine.
“They respected him,” George A. Stamboulidis, Mr. Weissmann’s trial partner, said of his colleague and their mob witnesses. “He’s very bright and to the point but also has a pretty good read of his audience. It was definitely a relationship of mutual respect.”
Geoffrey S. Mearns, a former prosecutor in the Eastern District who is now the president of Ball State University in Indiana, said Mr. Weissmann’s personality mirrored that of the office — with its collection of scrappy, ambitious obsessives out to prove their relative mettle in a city where another office, the Southern District in Manhattan, was often viewed as more prestigious.
That their targets were some of the city’s most fearsome murderers tended to focus the mind, as well.
“He was trained in this environment that we were essentially going after these entrenched mob bosses,” Mr. Mearns said. “He’s trained as a prosecutor to be aggressive.”
‘I Don’t Drink Evian’
The locals did not all take well to their visitors from the federal government, dispatched to Houston after the collapse of Enron to investigate and prosecute the company’s fraud.
“Out-of-town, carpetbagging, Evian-swilling Department of Justice lawyers,” read one description in The Houston Chronicle.
This was an outrage, Mr. Weissmann told a reporter then. “I don’t drink Evian.”
It was this swagger that helped define the government’s posture as the task force went about its work, first with Mr. Weissmann as deputy director, then later as director. (Mr. Mueller, as F.B.I. director at the time, helped form the group.)
Their triumphs were many: With little precedent for such a complex inquiry into financial wrongdoing, the team won indictments and prison terms for almost all of the company’s top executives.
Mr. Weissmann was credited with acting on a hunch that Ben F. Glisan Jr., the former Enron treasurer who had already pleaded guilty without agreeing to cooperate, might be willing to say more. United States marshals hauled in Mr. Glisan from prison, at Mr. Weissmann’s direction, to appear before a grand jury. He became a key witness.
Prosecutors also initially earned a conviction of Arthur Andersen, an accounting firm charged with illegally destroying documents related to its audit of Enron, for obstruction of justice.
Colleagues praised his resourcefulness and legal guile. Opponents accused him of overreach, citing a series of overturned convictions and higher-court losses. Among the setbacks for the task force, the Arthur Andersen victory was unanimously overturned by the Supreme Court over a narrow issue involving jury instructions. Long before that outcome, the case had drawn ferocious criticism from members of the business community, who argued that the indictment alone amounted to a death sentence for the firm.
“It’s pretty clear that Weissmann created a culture in which they presumed that the people they were investigating were guilty,” said Tom Kirkendall, a Houston defense lawyer who represented clients on Enron-related cases.
This reputation has trailed Mr. Weissmann among some defense lawyers in the years since, propagated most vocally by a lawyer and author, Sidney Powell, whose work has been taken up by Trump allies like Newt Gingrich. (In 2015, Ms. Powell criticized Mr. Weissmann in an article for The New York Observer — which was owned by Jared Kushner, Mr. Trump’s son-in-law — after Mr. Weissmann was named to lead the Justice Department’s criminal fraud section.)
But those close to Mr. Weissmann — and some others less inclined to appreciate the work of prosecutors generally — have zealously defended his ethical compass.
Peter Neufeld, a civil rights lawyer and co-founder of the Innocence Project, praised Mr. Weissmann’s nerve during his time at the F.B.I., as the agency grappled with the fallout of exonerations based on erroneous testimony from forensic hair examiners.
“He realized that what had gone on in the past was wrong,” Mr. Neufeld said, recalling Mr. Weissmann’s decision to order an audit of hundreds of convictions that may have relied on faulty testimony. “He did it. That was transformative.”
By 2013, both Mr. Weissmann and Mueller had left the agency. It seemed unlikely that they would partner again.
Then came the call last spring.