In what appears to be the first ruling of its kind, a New York judge will allow a lesbian couple who married in Canada to sue for divorce.

Though New York does not allow same-sex marriages, a state trial court judge refused to dismiss a divorce and child custody suit brought by a woman, identified only as Beth R., against her former partner Donna M.

Donna M. had argued that her 2004 marriage should be invalid in New York because the state doesn’t allow same-sex marriage, but Supreme Court Justice Laura Drager found that the out-of-state marriage could still be recognized under New York law. Her ruling appears to be the first divorce case in New York from a same-sex marriage.

“What we’re seeing now is a judicial battle that’s going to be waged in [the] next few months,” said Arthur Leonard, who teaches a class on sexual orientation and the law at New York Law School. “People sometimes forget that divorce is part of marriage. People need a judicial process to untangle a relationship.”

In her ruling Monday, Drager said New York will not recognize an out-of-state marriage only if it is prohibited by a state law or if it is “abhorrent to New York public policy.” She said only polygamy and incest have been found to be abhorrent.

Beth R. and Donna M., described as in their 40s and working in the media industry, were married in Toronto in 2004. They have two daughters, both born to Donna M.

Read more at ABC News: In First, N.Y. Judge Allows Gay Divorce