Jacob Gershman in the Wall Street Journal today reports on the Louisiana same-sex marriage ruling.

A U.S. district judge on Wednesday upheld Louisiana’s ban on same-sex marriage, breaking with the vast majority of federal courts on a constitutional question likely to be settled by the U.S. Supreme Court.

Acknowledging he was sounding a discordant note amid a “hopeful chorus” of recent rulings, U.S. District Judge Martin Feldman said he was unconvinced that gay couples have a constitutional right to marry. The judge said federal court decisions striking down gay marriage bans “exemplify a pageant of empathy,” but he doubted their legal wisdom.

“This Court is persuaded that Louisiana has a legitimate interest…whether obsolete in the opinion of some, or not, in the opinion of others…in linking children to an intact family formed by their two biological parents,” wrote Judge Feldman, leaving in place a state constitutional ban backed by 78% of Louisiana voters in a 2004 referendum.

The ruling ends a remarkable winning streak for the marriage-equality movement. Since the Supreme Court in 2013 invalidated Defense of Marriage Act provisions denying federal benefits to same-sex spouses,19 different federal courts have ruled against same-sex marriage bans in 16 states, according to Lambda Legal, a national gay rights legal group. Two other federal courts had ruled against gay plaintiffs in Hawaii and Nevada in older cases filed before last year’s high-court decision.

The string of victories also includes two appellate courts, the 10th U.S. Circuit Court of Appeals in Denver and the Fourth U.S. Circuit Court of Appeals in Richmond, Va. Two other circuit courts are expected to weigh in with decisions this year.

Judge Feldman, a Reagan appointee, said the momentum behind gay marriage may seem “ordained.” But the movement, he said, faces “inconvenient questions,” echoing the slippery-slope argument made by many defenders of traditional marriage laws. Wrote the judge:

For example, must the states permit or recognize a marriage between an aunt and niece? Aunt and nephew Brother/brother? Father and child? May minors marry? Must marriage be limited to only two people? What about a transgender spouse? Is such a union same-gender or male-female? All such unions would undeniably be equally committed to love and caring for one another, just like the plaintiffs.

Gay marriage opponents seized on the ruling as a tide-turning triumph for their side. “Here we see the house of cards collapsing that supported the myth that redefining marriage in inevitable,” Brian S. Brown, president of the National Organization for Marriage, said in a statement.

State attorneys general in Utah and Virginia have asked the Supreme Court to overturn lower-court ruling striking down state bans. In a crowded field of litigation, the Louisiana case is unlikely to make a dent, said Kenneth Upton, senior counsel with Lambda.

“I wouldn’t call it a game-changer. I’d call it an outlier,” Mr. Upton told Law Blog. “It’s very unlikely that cases that just now are coming along at the trial level are far enough along to have much impact on the ultimate result.”

Nineteen states, as well as the District of Columbia, currently authorize same-sex marriage.