Pittsburgh City Council gave its tentative approval today to legislation that would allow unmarried couples to be listed on a "domestic registry" that employers could voluntarily consider when deciding on whether to allow the sharing of employee benefits.

Friends, straight or gay couples, cohabitating seniors and others could walk into the City-County Building, show evidence of their "mutual commitment," and pay $25 to be registered. Registered city employees could share their fringe benefits with partners.

Acting on the advice of the city solicitor's office, council clarified language to disallow non-city-residents from registering.

Under the legislation, any two unmarried city residents -- unless they are related too closely to be married under state law -- could apply with the city Personnel Department. They would have to show three pieces of documentation of "mutual responsibility," which can include loan papers, utility bills, insurance policies, wills, powers of attorney, contracts, motor vehicle titles, bank or credit account statements, or evidence of shared child care responsibility. The resulting designation would apply until one party either presented an affidavit ending the relationship or died.

Only Councilman Ricky Burgess voted no. A final vote is set for Tuesday.