The voluminous brief, filed late Monday ahead of a midnight deadline, is the first step in a process leading to an April 10 hearing before the 10th U.S. Circuit Court of Appeals in Denver..

The court then will decide if it agrees with a federal judge in Utah who in mid-December overturned the 2004-voter passed ban, saying it violates gay and lesbian couples’ rights to due process and equal protection under the 14th Amendment. The appeals court also is reviewing a similar decision about Oklahoma’s ban, and a hearing on that case has been set for April 17.

Attorneys for three gay and lesbian couples who sued Utah have until Feb. 25 to respond.

The state contends redefining marriage poses “real, concrete risks to children” because not having a mother or father leads to emotional damage. The state said its duty is to look out for the long-term interests of children who can’t defend themselves. The state also believes allowing same-sex marriages would lead to reduced birth rates, which would bring demographic and economic crisis.

“The diversity of having both a mom and a dad is the ideal parenting environment,” wrote Gene Schaerr, an outside attorney who has been hired by the state to defend the law. “That model is not intended to demean other family structures, any more than giving an A to some students demeans others.”

The state made similar arguments in court papers filed before the U.S. Supreme Court in early January when it asked the justices to halt gay marriages that were occurring in Utah. The high court approved the request, granting an emergency stay while the 10th Circuit considers the case.

Attorneys representing three gay and lesbian Utah couples scoffed at the notion gay and lesbian couples make inferior parents, saying the state provides no scientific evidence to back its claim.

Shannon Minter, legal director for the National Center for Lesbian Rights, said Tuesday the state’s brief offers no justification for harming sex-sex couples and their families. The organization is teaming with a pair of Salt Lake City attorneys to handle the case.

“It’s disappointing that the Utah officials’ brief shows no understanding of the common human needs that gay and lesbian people share with all others, and how marriage strengthens all families, including families of same-sex couples and their children,” she told The Associated Press.

Minter added Utah’s argument is at odds with the U.S. Supreme Court’s ruling last summer striking down part of the Defense of Marriage Act. In that decision, the justices wrote limiting marriages to a man and a woman relegates gay marriages to second-class status and “humiliates tens of thousands of children now being raised by same-sex couples.”