Mr. Weinstein, who was fired by the movie and television studio he co-founded, the Weinstein Company, has denied rape allegations while acknowledging that his behavior “caused a lot of pain.”
Although largely symbolic, the ouster of Mr. Weinstein from the roughly 8,400-member academy is stunning because the organization is not known to have taken such action before — not when Roman Polanski, a member, pleaded guilty in a sex crime case involving a 13-year-old girl; not when women came forward to accuse Bill Cosby, a member, of sexual assault; and not when Mel Gibson went on anti-Semitic tirade during a drunken-driving arrest in 2006 or pleaded no contest to a charge of battery against an old girlfriend in 2011.
Now, the academy may be forced to contend with other problem members.
Scott Feinberg, the longtime awards columnist for The Hollywood Reporter, said, “This may well be the beginning of a very tough chapter for the academy. The next thing that is going to happen, rightly or wrongly, is that a wide variety of constituencies are going to demand that the academy similarly address other problematic members.”
Mr. Feinberg added that he was speaking of academy members like Mr. Polanski and Stephen Collins, the “7th Heaven” actor who admitted in 2014 that he molested teenage girls in past decades, which resulted in police investigations in New York and Los Angeles but no charges.
Before Mr. Weinstein — who built two studios on the back of the Academy Awards, securing more than 300 nominations for his movies — only one person was known to have been permanently expelled from the academy. Carmine Caridi, a character actor, had his membership revoked in 2004 for violating an academy rule involving Oscar voting. He got caught lending DVD screeners of contending films; copies ended up online. (In the 1990s, a couple of people were temporarily suspended for selling their allotted tickets to the Oscar ceremony.)
The academy’s board, roughly 40 percent female, includes Hollywood titans like Steven Spielberg, Whoopi Goldberg, the Lucasfilm chief Kathleen Kennedy, Tom Hanks, the documentarian Rory Kennedy and Jim Gianopulos, the chairman of Paramount Pictures.
In an example of Mr. Weinstein’s reach, at least 10 governors have worked on films that he produced or that his studios have released. One board member, Christina Kounelias, now an executive vice president at Participant Media, started her career at Miramax, working in publicity for four years.
The board’s president is John Bailey, a cinematographer whose credits include “Ordinary People,” a winner of the 1981 Academy Award for best picture, and “Groundhog Day.” Lois Burwell, who is listed as its first vice president, is a makeup artist who won an Oscar in 1996 for her work on “Braveheart.”
The meeting of the board was called on Wednesday. In the days leading up to it, as the industry was grappling with new public accusations against Mr. Weinstein published in The New Yorker, The Times and on social media, some board members spoke among themselves to see if they could reach an informal consensus on how a vote on the mogul’s status would go.
Kathleen Kennedy, an eight-time Oscar nominee, told fellow board members that she was outraged by the allegations, according to a person briefed on advance discussions, who spoke on the condition of anonymity to comply with academy confidentiality strictures. But Ms. Kennedy was also said to be aware that pushing him out could put the academy on a slippery slope.
The Saturday meeting began at 10 a.m. and lasted until roughly 12:30 p.m. It was held inside a colossal conference room on the seventh floor of the academy’s mirrored-glass tower on Wilshire Boulevard in Beverly Hills. As with all academy board meetings, voting was anonymous. Some participants participated via speakerphone. Coffee and fruit were available.
The discussion was largely contained to Mr. Weinstein, according to two people there, but the board spent some time talking about the implications of censuring him. Mr. Polanski was one name mentioned.
In addition to the seriousness and plenitude of the allegations against Mr. Weinstein, the board concentrated on workplace abuse. Mr. Weinstein often used the pretext of meetings — casting sessions, script discussions — to lure women to hotel rooms, The Times and New Yorker investigations found.
It was not a heated discussion. “Everyone seemed aligned,” one board member said.
In outlining duties for the board of governors, the academy’s bylaws say, “Any member of the academy may be suspended or expelled for cause by the board of governors. Expulsion or suspension as herein provided for shall require the affirmative vote of not less than two-thirds of all the governors.”
No person has been more closely associated with the Academy Awards in recent decades than Mr. Weinstein, who won a best picture Oscar in 1999 for “Shakespeare in Love” and who orchestrated campaigns that resulted in more than 80 statuettes for films released by the studios he ran, including best picture Oscars for “Shakespeare in Love,” “The English Patient,” “Chicago,” “The King’s Speech” and “The Artist.”
The adulation afforded him power — so much power that many women feared reporting his alleged abuses — and gave him the credibility he was able use as a shield whenever rumors of his behavior started to swirl.
Starting in 1990, when he pushed a pair of foreign films, “My Left Foot” and “Cinema Paradiso,” to Oscar glory, Mr. Weinstein became famous for sharp-elbowed, ethics-be-damned campaign tactics. According to “Down and Dirty Pictures: Miramax, Sundance and the Rise of Independent Film,” Peter Biskind’s 2004 book about the indie film movement spurred by Mr. Weinstein’s Miramax studio, he once courted voters at a movie industry nursing home.
Initially horrified, the Hollywood establishment soon copied his playbook, turning Oscar season into a free-for-all. But Mr. Weinstein remained the maestro, peaking at the 2003 Oscars, when he had a hand in four of the five films nominated for best picture. (Miramax’s “Chicago” was the winner.)
Mr. Weinstein was such a force that year that The Los Angeles Times nicknamed the ceremony “the Harveys.”
He alternately charmed and bullied the trade press and glossy magazines, and the lavish parties he threw on the night before the Oscars ceremony became a status destination in Hollywood. The most recent Weinstein Company bash, held in February at the Montage Beverly Hills hotel, included among its guests Lin-Manuel Miranda, Jay-Z and Beyoncé.
His fall has come hard and fast. The first article to appear in The New York Times on women’s accusations against Mr. Weinstein was published on Oct. 5. While the authorities in New York and London are investigating Mr. Weinstein, no charges have been filed against him.
Pressure had been building on the academy to purge Mr. Weinstein. As actresses including Ashley Judd, Angelina Jolie and Gwyneth Paltrow came forward with horrifying tales and the British Academy of Film and Television Arts kicked him out, the academy released a statement condemning Mr. Weinstein’s alleged behavior as “repugnant, abhorrent” and saying it would meet on Saturday to discuss “any actions warranted.”
While the Academy of Motion Picture Arts and Sciences worked to corral its vast board, members started to come forward to demand action. A Change.org petition demanding that the academy banish Mr. Weinstein gathered more than 140,000 signatures.
The emergency academy meeting took place after employees and several board members fled the boutique movie studio Mr. Weinstein helped found as talk of bankruptcy swirled around it. On Friday, one person at the Weinstein Company, which has roughly 150 employees in New York and Los Angeles, described an operation in chaos, with phones going unanswered and some staff members in revolt.
Bob Weinstein, now scrambling to salvage the Weinstein Company, is facing mounting questions about what he knew about his brother’s behavior and why he did not intervene.
The Producers Guild of America was also scheduled to meet on Saturday to discuss revoking Mr. Weinstein’s membership. Late Friday, the group abruptly moved the special meeting to Monday. Under that group’s bylaws, Mr. Weinstein will have two weeks to respond to any action. The same guild gave the Weinstein brothers its Milestone award in 2013, citing their “historic contributions to the entertainment industry.”
In a sign of the international nature of the condemnation of Mr. Weinstein, the French government on Saturday said it had started a process that could strip him of his Legion of Honor, the country’s highest civilian distinction; he received it in 2012. A government spokesman had said that France would wait for definitive legal action before considering such action.
An earlier version of this article misstated the given name of the board of the motion picture academy. He is John Bailey, not Jim.