In a closed-door meeting this week in an undisclosed site near Baltimore, a committee of Jewish legal experts who set policy for Conservative Judaism will consider whether to lift their movement's ban on gay rabbis and same-sex unions.

In 1992, this same group, the Committee on Jewish Law and Standards, declared that Jewish law clearly prohibited commitment ceremonies for same-sex couples and the admission of openly gay people to rabbinical or cantorial schools. The vote was 19 to 3, with one abstention.

Since then, Conservative Jewish leaders say, they have watched as relatives, congregation members and even fellow rabbis publicly revealed their homosexuality. Students at the Jewish Theological Seminary in New York City, the movement's flagship, began wearing buttons saying "Ordination Regardless of Orientation." Rabbis performed same-sex commitment ceremonies despite the ban.

The direction taken by Conservative Jews, who occupy the centrist position in Judaism between the more liberal Reform and the more strict Orthodox, will be closely watched at a time when many Christian denominations are torn over the same issue. Conservative Judaism claims to distinguish itself by adhering to Jewish law and tradition, or halacha, while bending to accommodate modern conditions.

"This is a very difficult moment for the movement," said Rabbi Joel H. Meyers, a nonvoting member of the law committee and executive vice president of the Rabbinical Assembly, which represents the movement's 1,600 rabbis worldwide.

"There are those who are saying, don't change the halacha because the paradigm model of the heterosexual family has to be maintained," said Rabbi Meyers, a stance he said he shared. "On the other hand is a group within the movement who say, look, we will lose thoughtful younger people if we don't make this change, and the movement will look stodgy and behind the times."

Several members of the law committee said in interviews that while anything could happen at their meetings on Tuesday and Wednesday, there were more than enough votes to pass a legal opinion (a teshuvah in Hebrew) that would support opening the door to gay clergy members and same-sex unions. The law committee has 25 members, but only six votes are required to validate a legal opinion.

Committee members who oppose a change may try to argue that the decision is so momentous that it falls into a different category and requires many more than six votes to pass, even as many as 20, the members said. Other members may argue that no vote should be taken because the committee and the movement are too divided.

The committee may even adopt conflicting opinions, a move that some members say would simply acknowledge the diversity in Conservative Judaism. The committee's decisions are not binding on rabbis but do set direction for the movement.

"I don't think it is either feasible or desirable for a movement like ours to have one approach to Jewish law," said Rabbi Gordon Tucker of Temple Israel Center, in White Plains, a committee member who has collaborated with three others on a legal opinion advocating lifting the prohibition on homosexuality.

Even if the five Conservative rabbinical schools — in New York, Los Angeles, Jerusalem, Buenos Aires and Budapest — adopted different approaches, Rabbi Tucker said, "I don't think that would necessarily do violence to the movement."

The Conservative movement was long the dominant one in American Judaism, but from 1990 to 2000 its share of the nation's Jews shrank to 33 percent from 43 percent, according to the National Jewish Population Survey. In that same period, the Reform movement's share jumped to 39 percent, from 35, making it the largest, while Orthodox grew to 21 percent, from 16 percent. Estimates are difficult, but there are five to six million Jews in the United States.

Jonathan D. Sarna, a professor of American Jewish history at Brandeis University and author of "American Judaism: A History," said, "In the 1950's when Americans believed everybody should be in the middle, the Conservative movement was deeply in sync with a culture that privileged the center. What happens as American society divides on a liberal-conservative axis is that the middle is a very difficult place to be."

Rabbi Meyers, vice president of the Rabbinical Assembly, said he worried that any decision on homosexuality could cause Conservative Jews to migrate to either Reform, which accepts homosexuality, or Orthodoxy, which condemns it. But Dr. Sarna said some studies suggested that many Jews who were more traditional began abandoning the Conservative movement more than 20 years ago, when it began ordaining women.

Few congregants are as preoccupied about homosexuality as are their leaders, said Rabbi Burton L. Visotzky, a professor of Talmud and interreligious studies at the Jewish Theological Seminary, who spends weekends at synagogues around the country as a visiting scholar.

"There are so many laws in the Torah about sexual behavior that we choose to ignore, so when we zero in on this one, I have to wonder what's really behind it," Rabbi Visotzky said.

The ban on homosexuality is based on Leviticus 18:22, which says, "Do not lie with a male as one lies with a woman; it is an abomination," and a similar verse in Leviticus 20:13.

The law committee now has four legal opinions on the table. Although the reasoning in each is different and complex, two opinions essentially oppose any change to the current law disapproving of homosexuality, and one advocates overturning the law.

A fourth, authored by Rabbi Elliot N. Dorff, rector and a professor of philosophy at the University of Judaism in Los Angeles, argues that the passages in Leviticus refer only to a prohibition on anal sex and that homosexual relationships, rabbis and marriage ceremonies are permissible.

"What we're really trying to do is to maintain the authority of halacha, but also enable gays and lesbians to have a love life sanctioned by Jewish law and guided by Jewish law," said Rabbi Dorff, vice chairman of the law committee.

A change in the ban on homosexuality has been staunchly opposed by the longtime chancellor of the Jewish Theological Seminary, Rabbi Ismar Schorsch. But Rabbi Schorsch is retiring in June after 20 years, and his successor could greatly affect the policy. Rabbi Schorsch declined to be interviewed for this article. Several Conservative officials said that while Rabbi Schorsch is not a member of the law committee, he is very involved in its deliberations on this issue.

If the law committee does not vote to change the prohibition, some rabbis said, the issue could resurface at the Rabbinical Assembly's convention March 19-23 in Mexico City.

Many students at the seminary say they find the gay ban offensive and would welcome a change, said Daniel Klein, a rabbinical student who helps lead Keshet, a gay rights group on campus. "It's part of the tradition to change, so we're entirely within tradition," he said. Mr. Klein said that even if the law committee did not lift the ban this week, change would come eventually.

"Imagine what will happen 10 years from now when some of my colleagues are on the law committee, when people from my generation are on the law committee," he said. "It's not going to be a close vote."

• Copyright 2006The New York Times Company