In what is being hailed as a “terrific” victory for gay and lesbian parents, the U.S. Supreme Court on Monday reversed a decision of the Alabama Supreme Court that had refused to recognize a lesbian mother’s adoption of the children she raised from birth with the children’s biological mother.

The National Center for Lesbian Rights (NCLR) brought the case to the U.S. Supreme Court last November, hoping the court would hear oral arguments in the case this year. Instead, the high court voted unanimously to simply reverse the Alabama Supreme Court decision.

“We are thrilled by today’s unanimous decision,” said NCLR Legal Director Shannon Minter. Minter said the order confirms that the Alabama Supreme Court’s decision was such a “blatant violation of settled Full Faith and Credit principles that it warranted summary reversal without the need for further briefing or argument.”

“The order provides everything we were seeking for our client,” added Minter, “and also makes clear to other states that adoptions by same-sex parents must be given full faith and credit.”

The U.S. Supreme Court takes very few family law cases, noted Nancy Polikoff, a well-known expert in LGBT family law.

“It is extraordinary to have a per curiam opinion with no dissents treating [the same-sex couple case] as the pretty straight-forward kind of [adoption] case it should be treated as,” said Polikoff. “It is terrific….It’s a huge victory at every level.”

The March 7 order in V.L. v. E.L. was released “per curiam,” meaning without any one justice being identified as the author.

The case involved an adoption that took place in Fulton County, Georgia, in 2007. The adoptive mother, identified only as V.L. in court papers, adopted the three children she was helping to raise with her partner and the children’s biological mother, E.L. The two women agreed to use insemination to have the children.

After the adoption, the family moved to Alabama and later split up. The biological mother then sought to prevent the adoptive mother from having any contact with the three children, ages 14 and 11. That’s when V.L. filed suit for visitation and/or custody.

All this took place before the 2015 decision by the U.S. Supreme Court, striking down state bans against recognizing or licensing marriages for same-sex couples. Both Alabama and Georgia had bans on marriage for same-sex couples, and the women in this case were never married. So the Obergefell v. Hodges decision did not come into play, although Obergefell’s “affirmation that same-sex couples and parents must be treated equally certainly provides a helpful context,” said Minter.

In Alabama, the biological mother’s attorney argued that the adoption granted by Georgia was not valid in Alabama. The Alabama Supreme Court agreed, saying that the Georgia family court had not properly followed Georgia family law when it granted the adoption to V.L. (The Alabama court said Georgia should have first required the biological mother to surrender her rights to custody.)

NCLR argued that no state supreme court in the country had ever refused to recognize any out-of-state adoption “based on a disagreement with how the court issuing the adoption interpreted its own adoption laws.

“Because the Alabama Supreme Court’s decision was such a clear departure from established law,” said Minter, “we were hopeful the Court would summarily reverse, as they now have done.”

The U.S. Supreme Court in December granted a stay of the Alabama Supreme Court decision and ordered that the adoptive mother be allowed visitation with the children, pending the high court’s decision on whether to take the appeal. But on Monday, March 7, the eight members of the current U.S. Supreme Court (since Justice Antonin Scalia’s death last month) issued an order without oral argument: It reversed the Alabama Supreme Court’s ruling.

The Supreme Court ruled that the U.S. Constitution’s “Full Faith and Credit” clause requires each state to “give effect to valid judgments” of courts in other states.

“A state may not disregard the judgment of a sister State because it disagrees with the reasoning underlying the judgment or deems it to be wrong on the merits,” stated the Supreme Court order. It also noted that Georgia law gave the Georgia court that granted the adoption “exclusive jurisdiction in all matters of adoption.”

“It follows that the Alabama Supreme Court erred in refusing to grant that judgment full faith and credit,” said the order. In reversing the state supreme court decision, the Supreme Court order remands the case to the Alabama trial court, which initially granted the adoptive mother visitation.

Polikoff said she doesn’t think the Supreme Court ruling guarantees equal treatment of LGBT parents in custody battles in Alabama.

“Nothing the Supreme Court did today will stop Alabama courts from preferring straight parents as custodial parent. The vulnerability that we see in cases decided between gay and straight [parents] remains.” But, she added, “It’s an extraordinarily strong rebuke of more than two decades of Alabama courts disrespecting gay parents….The Supreme Court drew a pretty big line.”