A circuit court broke with other appeals courts, forcing the Supreme Court’s hand

It wasn’t until federal appeals courts disagreed on the constitutionality of states’ same-sex marriage bans that the Supreme Court decided to step in.

As lower courts struck down states’ same-sex marriage bans, many court watchers expected the Supreme Court to eventually take an appeal to decide the issue once and for all. But in October 2014, the Supreme Court refused to hear same-sex marriage cases from five states in which federal appeals courts had ruled in favor of marriage equality.

”[W]hen there’s no disagreement among the courts of appeals, we don’t step in,” Justice Ruth Bader Ginsburg explained at a 92nd Street Y event on October 19, 2014. “The major job that the court has is to keep the law of the United States more or less uniform. So when courts of appeals disagree about what the law of the United States is, then we are obligated to grant review.”

Up to that point, circuit courts had all ruled in favor of same-sex marriage rights, so at least six of nine Supreme Court justices reasoned that they didn’t need to interfere. This meant that the lower courts’ decisions stood — and marriage equality arrived in 11 states — but it also left the broader battle for another day.

That all changed a couple of weeks after Ginsburg’s public comments, when the Sixth Circuit Court of Appeals became the first federal appeals court to uphold states’ same-sex marriage bans in Kentucky, Michigan, Ohio, and Tennessee, on the basis that marriage rights should be left to the voters and legislatures of a state to decide. By disagreeing with previous federal appeals courts decisions, the court created a dispute among the federal appeals courts — one that only the Supreme Court could clear up.

Until the split, it was possible — although not likely — that all federal appeals courts could have ruled in favor of marriage equality, allowing the Supreme Court to remain out of the issue. But the split is why the Supreme Court heard same-sex marriage cases and brought marriage equality to all 50 states.