Boston ? Legislators opposed to gay marriage were coming up with ways Thursday to circumvent a Massachusetts court ruling that paves the way for same-sex marriages as early as May.

House Speaker Thomas Finneran, who opposes gay marriage, wants the high court to delay when its ruling takes effect until voters have considered a constitutional amendment defining marriage as a heterosexual union.

That measure has yet to be approved by the Legislature and wouldn’t appear on a ballot until 2006. But without the delay, the Democrat said Thursday, “You would have a period of time of complete legal chaos and confusion about the validity of those relationships.”

Under Wednesday’s 4-3 advisory ruling by the Supreme Judicial Court, gay marriages could begin in Massachusetts in mid-May. If voters were to pass the heterosexuals-only amendment, it is unclear whether marriages performed during the more than two years in between would be legally binding.

The court’s opinion Wednesday doused one compromise option, Vermont-style civil unions, ruling that they don’t go far enough because gay couples are entitled to all benefits of marriage.

Opponents of gay marriage pin their hopes on part of the original court ruling that said state law provided no “rational” basis for prohibiting same-sex couples from the benefits of marriage.

Some lawmakers, including Rep. Eugene O’Flaherty, hope to craft a bill providing such a rational basis for excluding gay couples from marriage while conveying some new benefits to same-sex couples.

“The court has overstepped its boundary and has not let the legislative process to unfold the way it has on other issues,” O’Flaherty said.

The much-anticipated opinion came a week before next Wednesday’s Constitutional Convention, where the Legislature will consider an amendment backed by Gov. Mitt Romney that would define marriage as a union between a man and a woman.

“We’ve heard from the court, but not from the people,” Romney said in a statement. “The people of Massachusetts should not be excluded from a decision as fundamental to our society as the definition of marriage.”

Senate President Robert Travaglini, who will preside over the Constitutional Convention, said he needed time to talk with fellow senators before deciding what to do next.