The Mormon Church filed a brief before the Tenth Circuit in opposition to same-sex marriage. (Photo from wikimedia by Joe Ravi)

The Mormon Church joined other major Christian groups on Monday in filing a legal brief supporting bans on same-sex marriage in Utah and Oklahoma, although they rely on a study that authors say shouldn’t be used as evidence against same-sex marriage.

The 53-page document urges the U.S. Tenth Circuit Court of Appeals to uphold bans on same-sex marriage on the argument that children are better off when raised by opposite-sex parents.

“Every child has a father and a mother,” the brief states. “Procreation within a stable male-female marriage gives a child a uniquely full human context that accounts for both the child’s biology and the deeper intentions and commitments of the child’s parents. The male-female ideal in marriage and parenting provides children security and other irreplaceable benefits.”

To bolster this argument, the brief on page 24 relies on a 2002 study from the D.C.-based non-profit Child Trends, titled “Marriage from a Child’s Perspective: How Does Family Structure Affect Children and What Can We Do About It?” The study makes no explicit reference to same-sex marriage.

But anti-gay groups have cited this study before in separate briefs filed before the Supreme Court last year in favor of California’s Proposition 8 and the Defense of Marriage Act — much to the objection of its authors who say their research says nothing about same-sex marriage.

Frank Walter, a spokesperson for Child Trends, reiterated that objection Tuesday in an email to the Washington Blade.

“Child Trends has been diligent in noting that it is inaccurate to make conclusions about the well-being of children being raised in same-sex households based on our study on heterosexual households,” Walter said. “As noted, this was not part of the study. In fact, we made this case in parliamentary hearings on this issue in Ireland when we were alerted that our information was being misrepresented.”

The study was also cited in the legal brief that the state of Utah filed last week before the Tenth Circuit in favor of its ban on same-sex marriage. The research also comes up in at least one other friend-of-the-court brief that was signed by social scientists and Mark Regenrus, who produced a discredited study against same-sex parenting.

Major psychological and family groups have disputed the notion that gay parents aren’t as fit as straight parents in raising children. Last year, the American Academy of Pediatrics came out in support of same-sex marriage.

Walter encouraged experts on the issue to research the issue of same-sex parenting because of the prevalence of LGBT families.

“We do not have data on children in same-sex families but hope research will be done in this area given the significant number of gay and lesbian families raising children,” Walter said.

The brief was filed in two separate cases related to same-sex marriage: one is the case filed against Utah’s ban, known as Kitchen v. Herbert, the other is the case filed against Oklahoma’s ban, known as Bishop v. Smith.

In addition to the LDS Church, other groups listed on the filing are the United States Conference of Catholic Bishops; National Association of Evangelicals; the Ethics & Religious Liberty Commission of the Southern Baptist Convention; and Lutheran Church—Missouri Synod.

The LDS Church is joining others in filing the brief despite an earlier media report from local Salt Lake City affiliate FOX 13 saying the church wouldn’t issue a filing in the case. The church didn’t immediately respond to a request for comment on why it was participating in filing despite this report.

Additionally, the brief cautions the court against striking down marriage bans on the basis that they adhere to the traditional concerns of morality, suggesting they should be upheld on the basis of freedom of religion.

“It follows that subjecting marriage laws and amendments to unusual constitutional scrutiny because they coincide with traditional morality would also raise grave First Amendment concerns,” the brief states. “Though differing religious groups may align on different sides of the marriage issue, judges cannot pronounce the religious beliefs of one set of voters progressive and another ignorant or hateful.”

The brief is along the lines of similar filings that the Mormon Church and other religious groups submitted before the U.S. Supreme Court last year when California’s Proposition 8 and the Defense of Marriage Act were before the court.

But there’s a key difference: even though the earlier filing included other groups, the only law firm in that document was the Salt Lake City-based Kirton & McConkie, which handles legal matters for the LDS church. Now, Anthony Picarello, general counsel for the U.S. Conference of Catholic Bishops, has joined that firm in signing the document before the Tenth Circuit.

Furthermore, the brief disputes the assertion often made by LGBT advocates (and courts) that bans on same-sex marriage were motivated out of animus toward LGBT people — a key consideration in determining the measures are unconstitutional.

“The accusation is false and offensive,” the brief states. “It is intended to suppress rational dialogue and democratic conversation, to win by insult and intimidation rather than by reason, experience, and fact. In truth, we support the husband-wife definition of marriage because we believe it is right and good for children, families, and society.”

John Gustav-Wrathall, senior vice president of the LGBT Mormon group Affirmation, said he concurs with the view the church isn’t motivated by animus in its opposition to same-sex marriage.

“There may be animus within the Mormon population, just as there is in the population at large,” Gustav-Wrathall said. “Some of that animus may fuel fervor for political activism against same-sex marriage. But generally we’ve seen tremendous progress in the understanding of LGBT people and of same-sex relationships in the church within recent years.”

The Mormon Church has been a key opponent of same-sex marriage after taking a lead role in passing Prop 8 in 2008. Although the church, with a few exceptions, largely stayed out the ballot fights in 2012, it was vocal against the legalization of same-sex marriage in Hawaii and has participated in legal cases to defend bans on same-sex marriage.