Now, Salt Lake City is poised to join a growing number of U.S. cities offering a domestic-partnership registry.

The voluntary index is considered a key tool for employers weighing whether to provide insurance benefits for same-sex couples and others who are financially interdependent.

Tonight the City Council is expected to vote - and likely approve - the registry proposed by new Mayor Ralph Becker.

"I don't know if it will get unanimous approval, but I think it will pass," said Councilman Eric Jergensen, who calls it a "natural extension" of the city's adult-designee ordinance. "When people understood what it was, they seemed to be less concerned."

Council members may tweak some language in the proposal, including the addition of a one-year waiting period after termination of a partnership before a person could re-register.

They appear less likely to mandate a one-year cohabitation requirement to establish eligibility.

Even so, the city's existing adult-designee ordinance requires one year before capital employees can receive domestic-partner benefits.

Becker insists the registry does not run afoul of Amendment 3, the provision of the Utah Constitution that prohibits same-sex marriage. And the City Council seems to agree.

The mayor argues the mechanism would save businesses time and money and create a way for the city to recognize relationships of mutual support, caring and commitment.

The proposed ordinance was crafted to extend eligibility to unmarried couples in either same- or opposite-sex relationships, including parent and child, other familial relationships and committed friendships.

Registrants, who would receive a notarized certificate to take to their employer, must be over 18 and share a primary residence in Salt Lake City.

If approved, the list administered by the city recorder should be ready for registrants later this month.

djensen@sltrib.com