Catholic Action League executive director C. J. Doyle called the proposed legislation, which would extend government-supported health care benefits to domestic partners of state, county, and municipal employees, "an assault on the consciences and pocketbooks of taxpayers."

"Domestic partner programs undermine the traditional family by creating a false and unwarranted equality between the institution of marriage on one hand, and homosexual and illicit heterosexual unions on the other," Mr. Doyle told members of the Legislature’s Joint Committee on Public Service.

"As the proponents of this legislation well know, it is a major incremental step towards the legalization of same gender marriages," he added.

Daniel Avila, associate director of public policy for the Massachusetts Catholic Conference, called the legislation "marriage redefinition bills crafted as heath care legislation."

The bills would make the phrase "domestic partners" legally equivalent with married spouses, he said.

The legislation also determines eligibility for benefits by examining the relationship for marriage-like qualities. These qualities include: sharing a household, exclusive commitment and mutual support, he said, adding that the bills do not use financial need as a criteria.

Mr. Avila said the Joint Committee on Public Service gave a favorable recommendation to the bills, which now await judgement from the Senate Ways and Means committee.

The Senate version of the bill may be brought to the floor during the summer, he said, adding that the legislation will likely pass the Senate with a voice vote.

If that happens, Speaker of the House Thomas M. Finneran will decide when and if the House votes on the legislation. Similar bills have passed both the Senate and House before being vetoed by Governor Paul Cellucci, Mr. Avila noted.

However, he said, Governor Jane Swift has not made her position on the legislation clear. Mr. Avila said a lawsuit brought against the state by the Gay and Lesbian Advocates and Defenders may play an important role in the domestic partners legislation’s future.

In April, seven domestic couples filed suit against the Department of Public Health and the state for prohibiting them from receiving marriage licenses, he said. The Department of Public Health issues marriage licenses.

The suit charges that the state’s decision violates the couples’ constitutional rights and suggests an expansion of the state’s marriage definition to include domestic partnerships, according to Mr. Avila said.

In doing so, the suit merges two issues that advocates of the domestic partners bills usually separate, the issue of gay marriages and that of financial equity for domestic partners.

This merging of issues, he said, may deter some members in the Legislature from voting for the bills.