ANNAPOLIS, Md. (AP) – With same-sex marriage a no-go this year, Maryland senators voted March 18 to allow unmarried couples more rights to make medical decisions for each other.

The Senate voted 30-17 to allow domestic partners, who could be gay or straight, to make medical or funeral decisions for each other if they meet certain criteria to show they are a committed couple.

Unwed couples would have to show “mutual interdependence” such as joint checking accounts or common property ownership before qualifying as domestic partners eligible for the decision-making powers.

The bill comes amid complaints from unwed couples that they are sometimes denied life-or-death decision rights or medical privileges such as riding in an ambulance or visiting a partner on life support.

The measure now heads to the House. It could become the most substantive gay-rights matter lawmakers take up this year. This is the first general session of the legislature since Maryland’s highest court said last year that the legislature is free to remove gender definitions in state marriage law, but top lawmakers have said gay unions won’t be considered this term.

Supporters of the medical bill approved last Tuesday argued that in lieu of same-sex marriage, lawmakers ought to at least allow medical decision-making powers for unmarried couples.

“We’re not willing to do the right thing and open up marriage to everyone in Maryland,” said Sen. Jamie Raskin, D-Montgomery, who supports same-sex marriage.

The bill sparked days of debate from senators who questioned how couples would designate each other their domestic partners. Some also questioned whether the bill would open the door to same-sex marriage later.

“In society today, we promote marriage. Marriage between one man and one woman,” said Sen. Alex Mooney, R-Frederick, who opposed the measure. “You’re giving spousal rights to unmarried people.”

\The only Republican to support the bill, Sen. Allan Kittleman, said he wanted to allow couples who can’t marry for legal reasons the medical rights spouses have. He cited elderly couples and a widow who cannot marry her longtime partner because she’d lose benefits.

“I rise in support of this bill, and it’s not an easy thing for me to do,” said Kittleman, the Senate’s second-ranking Republican. Later, Kittleman added, “This isn’t simply about homosexuality.”

The legislature is also considering measures to exempt domestic partners from paying certain transfer taxes when one person dies, and a measure to add domestic partners to the list of people exempted from paying inheritance taxes.

Oddly, the bills have made allies in a way of gay-rights activists and gay-rights opponents. Gay-rights activists, citing a long debate over what-if scenarios made possible by the medical decisions bill, supported the medical bill but say lawmakers would be better to simply open marriage to gay couples.

“I think going down this road is going to illuminate legislators as to why marriage equality is the right answer,” said Dan Furmansky, head of Equality Maryland, the state’s largest gay-rights group.

And opponents of the medical bill said almost the same thing – that the medical bill is a step toward same-sex marriage. It’s an unusual alliance.

“It is kind of ironic how it’s worked out,” said the Rev. Rick Bowers, a Columbia pastor who is head of Defend Maryland Marriage, which opposes same-sex unions. “But it’s because we all see it as a step in the same direction. It’s an incremental step toward same-sex marriage.”