If voters in California thought that they’d heard the last word on same sex marriage when a majority of them approved a constitutional amendment banning it in 2008, they got another message with a federal judge’s ruling Wednesday.

And if Maine voters think that the issue was resolved once and for all with last year’s people’s veto vote, they too may be surprised.

The opinion of Chief Judge Vaughn Walker of the Federal District Court of San Francisco is not the last word, either — far from it. The decision will be appealed, probably ending up in the U.S. Supreme Court. Since it concerns California state law, the opinion does not directly affect Maine, although a Supreme Court decision could.

But the ruling is a reminder that this issue is far from settled, and that it will be a bone of contention in this society for some time. It’s also a reminder that in our system of government, it may be the courts and not the voters who end up with the last word.

The judge’s opinion is the first to follow a trial which tested the arguments people have made in political campaigns. Walker issued a series of factual findings that all sided with proponents of same-sex marriage.

He found no evidence that same-sex couples are worse parents, that their marriages detract from traditional couples’ or that allowing them to marry would cause any hardship for the state. Moral disapproval of homosexual behavior, which Walker found was at the heart of the campaign to outlaw same-sex marriage, was not enough to deny some citizens the right to marry. Neither, he said, was tradition, which alone “cannot form a rational basis for a law.”

In the modern world, he wrote, the partners in a marriage are legal equals, and the state’s demand that the institution should only be available to one man and one woman reflects “antiquated and discredited notions about gender” differences.

Same-sex marriage supporters in Maine say they have chosen to continue to try win over public opinion and change state law through the legislative process and the ballot box.

But it’s clear that the same arguments that were central in the referendum debate here were also argued in court, and before this question is finally settled, all three branches of government will have their say.