The Supreme Court confirmation hearings for Neil Gorsuch, which were held last month, in Washington, D.C., quickly fell into a pattern. Democratic senators unsuccessfully sought to pin down Gorsuch’s views on issues such as campaign finance, while Republicans made gentle inquiries that seemed designed to run out the clock. In this vein, toward the end of Gorsuch’s testimony, Ben Sasse, a Republican from Nebraska, asked Gorsuch his opinion about the Declaration of Independence. Gorsuch took the opportunity to deliver a patriotic lecture about the heroism of the Founders. “No one remembers who John Hancock was,” Gorsuch said. “But they know that that’s a signature because he wrote his name so bigly . . .” Gorsuch’s invocation of one of Donald Trump’s trademark utterances, apparently accidental, prompted an explosion of laughter from the audience.

Seated toward the back of the hearing room, Leonard Leo smiled. “There’s one sound bite,” he whispered to me, then added, “You know, the hearings matter so much less than they once did. We have the tools now to do all the research. We know everything they’ve written. We know what they’ve said. There are no surprises.” Gorsuch had committed no real gaffes, caused no blowups, and barely made any news—which was just how Leo had hoped the hearings would unfold.

Leo has for many years been the executive vice-president of the Federalist Society, a nationwide organization of conservative lawyers, based in Washington. Leo served, in effect, as Trump’s subcontractor on the selection of Gorsuch, who was confirmed by a vote of 54–45, last week, after Republicans changed the Senate rules to forbid the use of filibusters. Leo’s role in the nomination capped a period of extraordinary influence for him and for the Federalist Society. During the Administration of George W. Bush, Leo also played a crucial part in the nominations of John Roberts and Samuel Alito. Now that Gorsuch has been confirmed, Leo is responsible, to a considerable extent, for a third of the Supreme Court.

Leo, who is fifty-one, has neither held government office nor taught in a law school. He has written little and has given few speeches. He is not, technically speaking, even a lobbyist. Leo is, rather, a convener and a networker, and he has met and cultivated almost every important Republican lawyer in more than a generation. At the Gorsuch hearings, which took place in the Hart Senate Office Building, Leo acted as the unofficial mayor of the room. Sometimes he sat in the back, so that he could kibbitz with reporters, and sometimes he sat up front, behind Trump Administration officials. (Leo has been on leave from the Federalist Society to work full time on Gorsuch’s confirmation.) “When Leonard walks in that room, everyone knows who he is,” Carrie Severino, the chief counsel of the Judicial Crisis Network, another conservative organization that worked on Gorsuch’s behalf, said. “If you care about the conservative legal movement, you always take note of Leonard.”

Leo is at ease in the role of impresario. His grandfather was a vice-president of Brooks Brothers, and he instilled in young Leonard a taste for the bella figura. Leo wears tailored suits, often with contrasting waistcoats, and a double-length gold fob attached to a 1935 train conductor’s pocket watch. (“The most accurate watch in the United States until the fifties,” he said.) In lieu of office meetings, Leo prefers to chat over breakfast (just bacon, no eggs) at the Hay-Adams Hotel, across from the White House. As his friend Boyden Gray, the White House counsel under George H. W. Bush, puts it, “He knows the best restaurants in every major city in the world, and the best wines. He has a wide-ranging, inquiring mind, and he can and will talk about any subject under the sun.”

Leo’s role in the judicial nominations has drawn fierce criticism from liberals. Nan Aron, who is the longtime president of the Alliance for Justice, which advocates for a progressive judiciary, told me, “The Federalist Society has for years been singularly focussed on building a farm team of judicial nominees who subscribe to a philosophy that is hostile to the advancement of social and economic progress in the country. Behind the scenes, during Republican Administrations, they are very engaged in identifying and recruiting for judges candidates who are ultra-conservatives—who are opposed to our rights and liberties across the board, whether it’s women, the environment, consumer protections, worker protections.” Gorsuch is likely to be only the first of Leo’s Trump Administration appointees: he is preparing for yet more vacancies on the Supreme Court, and also finding candidates for some of the hundred-plus vacancies on the lower courts, deepening his imprint on the judiciary.

Leo’s life has been shaped as much by Catholicism as by conservatism. He was born on Long Island, and his father died, of cancer, when he was a preschooler. When Leo was five, his mother got remarried, to an engineer, and the family moved to central New Jersey, where Leo spent most of his childhood. His grandfather emigrated to the United States from Italy when he was fourteen and became a tailor before working his way up at Brooks Brothers. “He understood America as being a land of opportunity, understood the value of capitalism, the value of hard work, personal responsibility,” Leo told me. “My grandparents were deeply religious people, they were daily Mass attendees. So I got all of that.”

Leo went to college at Cornell, where he studied with a group of conservative professors in the government department. That led to internships in Washington during Ronald Reagan’s Presidency—notably for Senator Orrin Hatch, who was then, as now, a member of the Judiciary Committee. Leo went on to law school, also at Cornell, after which he returned to Washington and clerked for a federal appellate judge, A. Raymond Randolph, on the D.C. Circuit.

In the meantime, he had married his high-school sweetheart, Sally Schroeder. In 1992, they had their first child, Margaret, who was born with spina bifida, which confined her to a wheelchair and led to other medical complications. “She was a real miracle, despite having a really serious handicap, and many other issues, too,” Leo said. “She was extraordinarily vivacious, talented, simple. She had a great way with people.” Clarence Thomas, Leo said, still keeps her drawings under glass on his desk.

Margaret’s example deepened Leo’s Catholic faith. She encouraged him to go to daily Mass, though he found keeping up attendance difficult. During a family vacation in 2007, when Margaret was fourteen, Leonard promised her that he would resume the practice. On the morning after they returned, Leo got up early to go to Mass. He looked in on Margaret. Then, as he was walking down the hall, she started gasping for breath. She died shortly afterward. “I will always think that she did her job,” Leo told me. “She did her job.”

The Leos have six other children, including an eight-year-old son who also has spina bifida. A friend of Leo’s said, “Leonard comes to his pro-life views out of a place of incredible sincerity. They always treated Margaret throughout her life like any other child.” According to Leo, the vast majority of abortions are a consequence of voluntary, consensual sexual encounters, an opinion that influences his view of the procedure.“We can have a debate about abortion,” he told me. “It’s a very simple one for me. It’s an act of force. It’s a threat to human life. It’s just that simple.”