One Knox County couple's custody case is on track to set a parenting precedent for the state of Tennessee.

In April 2014, Erica and Sabrina Witt wed in Washington D.C., which recognized same-sex marriages at the time. The couple soon set about the task of becoming mothers together.

Through artificial insemination with sperm from an anonymous donor, Sabrina became pregnant and gave birth to a child in January 2015.

Erica never formally adopted the baby.

As her attorney Virginia Schwamm explained, "she didn't think she needed to."

As a legally married woman, Erica planned on spending the rest of her life with Sabrina and their child.

In June 2015, the U.S. Supreme Court ruled in favor of the plaintiffs in Obergefell v. Hodges, effectively striking down states' bans on same-sex marriage.

That meant the state of Tennessee had to recognize the Witts' marriage.

Now, the state is recognizing the couple's divorce. However, where the law is unclear is in regard to child custody.

"There hasn't been a case before on these facts, where...the parties were legally married, and there was an artificial insemination, and a child was born during the marriage, and the parties lived together, and raised the child together, and then there's a divorce," Schwamm said.

Tennessee state law is clear when it comes to custody proceedings involving a man and a woman's biological child.

The Witts' situation, however, is new territory. As they are in the midst of divorce proceedings, they're also mired in a custody battle.

On Friday morning, Fourth Circuit Court Judge Greg McMillan ruled Erica is not the legal parent of the child. She has the rights of a stepparent, but not a full, biological parent. That precludes her from making decisions about the child's life, including medical and school-related decisions.

Schwamm had asked the judge to apply the state's existing child custody laws, and apply "spouse and spouse" where the language specified "mother and father" or "husband and wife."

"He didn't think he could extend the law the way we were asking him to, and so he stuck with a very narrow ruling," Schwamm said.

The judge granted Schwamm's motion to take this case to the Tennessee Court of Appeals.

That came as a surprise to nobody, including Sabrina's attorney John Harber.

"I knew from the very moment that my client came in that this was an issue that was going to go to the appellate level," Harber said.

Schwamm said regardless of which side received its desired ruling Friday morning, the other side would be appealing to higher courts.

"This is just the first rung in a long, tall ladder," Harber said. "This case is going to go through the appellate process, and it's going to take awhile to climb to the Court of Appeals and probably ultimately to the (Tennessee) Supreme Court."

For now, the baby remains in Sabrina's custody, and Erica has limited visitation.

Tennessee's current custody laws date back to 1977, Harber said, and use language specific to heterosexual couples.

"You know, in 1977, 40 years ago, our general assembly was not thinking about same-sex marriage," Harber said, adding, "it really is something that, if it is to be changed, it should be done legislatively."

It will be up to higher courts to determine whether Tennessee's current law can be interpreted to apply to same-sex couples, too, or whether that's a matter for the Legislature.

Though, as Harber pointed, out, "our state Legislature is so conservative at this moment in time, I just think that's not going to happen."