Rick Bowmer, Associated Press
Utah has filed court documents asking a federal judge to throw out a lawsuit challenging a Utah voter-approved constitutional amendment that defines marriage as between a man and a woman.

SALT LAKE CITY — Traditional marriage encourages responsible child bearing and the best parenting, according to state attorneys defending Utah's definition of marriage.

Those are among the arguments the state made in court documents asking a federal judge to throw out a lawsuit challenging a Utah voter-approved constitutional amendment that defines marriage as between a man and a woman.

At the same time, lawyers for three gay and lesbian couples want U.S. District Judge Robert Shelby to strike down Amendment 3 and bar the state from enforcing its "marriage discrimination" laws. They contend the law is unconstitutional under the due process and equal protections clauses of the 14th Amendment.

The first hearing in the case is scheduled for Dec. 4.

Gay couple Derek Kitchen and Moudi Sbeity and lesbian couple Laurie Wood and Kody Partridge filed the lawsuit in March after Salt Lake County denied them marriage licenses. Karen Archer and Kate Call, who were legally married in Iowa, joined the suit because Utah does not recognize their marriage as valid.

The state says the case doesn't turn on who is right and who is wrong about what marriage should be, but on who should decide. The Constitution does not prevent Utahns from defining marriage as between a man and a woman with children's interests at the forefront, the Utah Attorney General's Office argues.

"The resolution of this case will determine much more than whether marriage licenses will be issued to some same-sex couples. It will necessarily impact whether Utah or any other state can maintain the principle that children should be reared by a married mother and father whenever possible ... "

According to the state, "the traditional definition of marriage rationally promotes legitimate state interests in promoting responsible procreation, and in promoting the optimal mode of child rearing, among others."

Peggy Tomsic, a Sat Lake attorney who represents the three couples, argues in court documents that the Constitution demands that people be free to marry whom they chose without the state infringing on that choice.

The purpose of the state's Amendment 3 was to "further privately held moral views that same-sex couples are immoral and inferior to opposite-sex couples," she wrote.

Utah law hurts children who are being reared by same-sex couples, she said. It makes it "more difficult for the children to understand the integrity and closeness of their own family and its concord with other families in their community and their daily lives," Tomsic wrote, quoting last summer's U.S. Supreme Court decision on the Defense of Marriage Act.

The justices struck down the section of the DOMA that defines marriage as between a man and a woman for purposes of federal law, ruling that the government must provide the same benefits to gay married couples as it does to heterosexual married couples.

The court also ruled that the traditional marriage activists who put Proposition 8 on California ballots in 2008 did not have the constitutional authority, or standing, to defend the law in federal courts after the state refused to appeal its loss at trial. The decision left in place a lower federal court decision that overturned Proposition 8 and effectively legalized gay marriage in California.

Tomsic contends Utah's refusal to recognize same-sex marriages in other states is unconstitutional under the Supreme Court decision.

Attorneys for the state say federal law allows Utah to reject same-sex marriages performed in other states.

"Even before DOMA, it was thoroughly well-settled that Utah need not recognize out-of-state marriages that are illegal if performed in Utah," they wrote.

New Jersey became the 14th state to permit gay marriage Monday when Gov. Chris Christie dropped the state's legal challenge to same-sex marriage, reversing his long-held position that voters not the judiciary should decide the issue.

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