Same-sex marriage is on the backburner in Tasmania after an attempt to re-introduce it to the state's upper house failed.
Independent member Ruth Forrest's motion to have legislation debated for a second time in the legislative council has been defeated 8-6.
Tasmania looked likely to become the first jurisdiction in the country to allow gay marriage when its lower house last year passed a bill, co-sponsored by premier Lara Giddings and Greens leader Nick McKim.
But the audacious bid came unstuck when the upper house voted it down, also 8-6.
The island state has since been beaten to the punch by the ACT, which passed a bill earlier this month.
Ms Forrest said new legal advice from constitutional expert Bret Walker SC showed Tasmania could pass its own laws on marriage.
"Even though the Commonwealth has covered the field of marriage, there is no potential conflict with same-sex marriage and therefore no question of constitutional invalidity," Ms Forrest told the house.
She said a federal government challenge in the High Court to the ACT's move was not relevant to Tasmania because it referred to the law governing territories, not the constitution.
"If we refuse to debate it, we'll look increasingly out of step with a society that is willing to grapple with this issue," Ms Forrest said.
Tasmania's 15-member upper house contains 12 independents, two Liberal members and one Labor MP.
Liberal members in both houses have opposed the bill.
"All of these issues have been canvassed before, so in my view there is nothing new," Liberal MLC Vanessa Goodwin said.
Marriage equality advocate Rodney Croome vowed to fight on, but suggested members were unwilling to accept the reform.
"(The constitutional) concerns have now been addressed, but they still voted against the bill, showing that in reality they just don't want to deal with this legislation," Mr Croome said in a statement.
Save Marriage Coalition spokesman Guy Barnett called it a "victory for common sense".
"Marriage is a bedrock institution between a man and woman worthy of protection," he said.
"It provides an umbrella under which children are nurtured and grow."
Same-sex marriage joined voluntary euthanasia as major attempts at social policy from the Labor-Green state government which have failed this year.
A vote on voluntary euthanasia, also co-sponsored by Ms Giddings and Mr McKim, was narrowly defeated in the lower house earlier this month.
"The legislative council has delivered mediocrity for Tasmania, and they have once again held our community back just when it was ready for change," Mr McKim said.