The Montgomery County Council approved legislation yesterday extending health benefits to the live-in partners of homosexual county employees, becoming the largest Washington area jurisdiction to enter the national debate over gay rights in the workplace.

Nearly 3,000 private-sector companies now offer domestic-partner benefits to homosexual employees, who are legally prohibited from marrying their partners and could not otherwise claim them as health insurance beneficiaries.

Dozens of local governments also extend those benefits, provoking sharp criticism from conservatives and religious organizations that contend the recognition is a step toward legally sanctioning gay marriage. Virginia Attorney General Mark L. Earley (R) sided this week with plaintiffs challenging Arlington County's domestic partners law, passed by the County Board two years ago but invalidated by a circuit court judge in March. The state Supreme Court is scheduled to hear the case early next year.

By a 6 to 3 vote, the Montgomery council followed Baltimore and Takoma Park to become the third Maryland jurisdiction to extend domestic-partner benefits to county employees. County officials predict that only a small fraction of Montgomery's 8,000 workers will add same-sex partners to their health plans--perhaps fewer than 100--and that the annual cost to county taxpayers will be less than $400,000.

As in many jurisdictions that offer such benefits, the public employees who qualify say the issue is about ensuring equal access to health care. But Montgomery lawmakers cast the measure as a way of ending discrimination based on sexual orientation.

"This is not a benefits bill. This is a bill to combat discrimination," said council member Derick Berlage (D-Silver Spring), the measure's lead sponsor.

The council vote inflamed social conservatives, who say the measure undermines the institution of marriage by extending similar rights to homosexual couples. In the front row of the council hearing room, members of the Women's Christian Temperance Union raised yellow signs imploring council members: "Say No to Sodomy Subsidies."

Bunny Galladora, national public relations director for the group, said the temperance union is consulting with lawyers to determine ways of preventing the bill from becoming law. A civic group called Montgomery County Watch immediately announced plans for a petition drive to put the question on a ballot for county voters to decide.

"This bill, when made law, will benefit those who are engaging in the unnatural, immoral and illegal act of sodomy," said Galladora, who declined to discuss the size of the temperance union's membership.

To make the bill more palatable to some wavering members, council members deleted a passage that read: "an employee's partnership with a person of the same sex can have all the attributes of a marriage except the legal recognition of marriage." Council member Blair G. Ewing (D-At Large), a reluctant supporter of the bill, said: "Marriage has a very special meaning in law and among people of many organized religions. So I don't like that finding."

Other council members expressed concerns about the process by which the benefits were being granted. Council member Marilyn Praisner (D-Eastern County) said giving such benefits to county employees, the vast majority of whom are union members, undermined the collective bargaining process that determines salary and benefits packages. "I do not believe the executive can go to the table in a give-and-get process if we give it all away outside those negotiations," she said.

County Executive Douglas M. Duncan (D) said yesterday he will sign the bill. "This is an equity issue, and the costs here are minimal enough that it doesn't cause me a great deal of worry," Duncan said. "This is something we can do."

The number of companies offering domestic partners benefits has grown this decade from a few dozen to almost 3,000, according to the Human Rights Campaign, the nation's largest political organization for gay men and lesbians. The companies include some of the region's largest employers, such as Marriott International and Bell Atlantic. The Washington Post Co. also extends health benefits to same-sex partners of its employees.

Many firms offer the incentives to help recruit and retain employees in a drum-tight market, but they typically do not extend the benefits to unmarried heterosexual couples. Council members rejected a proposal by council President Isiah Leggett (D-At Large) to extend health benefits to the live-in partners of heterosexual employees because those workers are legally allowed to marry.

Council members Berlage, Ewing, Leggett (D-At Large), Steven A. Silverman (D-At Large), Philip Andrews (D-Rockville) and Michael L. Subin (D-At Large) supported the bill. Council members Praisner, Nancy Dacek (R-Upcounty) and Betty Ann Krahnke (R-Potomac-Bethesda) voted against it.

To qualify live-in partners for health benefits, county employees must prove they have shared the same legal residence for at least one year, signing an affidavit under penalty of perjury to support the claim.

"It means I will be getting the same benefits as other county employees," said Reginald Jetter, a division chief in the county permitting department whose partner has been without health insurance for the five years they have lived together. "It relieves a lot of the anxieties my partner and I have about health care and the cost of health care."