A federal trial court ruled that Nevada can limit marriage to opposite-sex couples in a ruling made public hours before the Supreme Court is due to consider whether it will hear any of several cases addressing same-sex couples' marriage rights.

Judge Robert C. Jones, a George W. Bush appointee, found that the U.S. Constitution's guarantee of equal protection of the laws does not "[prohibit] the People of the State of Nevada from maintaining statutes that reserve the institution of civil marriage to one-man–one-woman relationships."

Jones ruled that a prior Supreme Court precedent — a 1972 case, Baker v. Nelson, that denied a same-sex couple's marriage claim as lacking any "substantial federal question" — controlled his decision. Even if not, he ruled that the "exclusion of same-sex couples from the institution of civil marriage" was constitutional "[b]ecause the maintenance of the traditional institution of civil marriage as between one man and one woman is a legitimate state interest."

In reaching his decision, Jones found that a classification like Nevada's marriage law, which distinguishes between heterosexual and homosexual people (his analysis did not address bisexuality), should not be viewed with additional scrutiny, as are laws that distinguish based on sex or race. The analysis, made as part of challenges claiming a violation of the Constitution's equal protection guarantees, asks whether the group claiming discrimination under the law has experienced a history of discrimination and continues to face levels of political powerlessness.

In these areas, Jones found — contrary to a recent decision by the Second Circuit Court of Appeals — that gay and lesbian people did not exhibit the characteristics necessary for additional protection.

"Homosexuals have not historically been denied the right to vote, the right to serve on juries, or the right to own property," he wrote, in dismissing claims of a history of discrimination. Noting recent ballot successes on marriage issues, Jones wrote, "It simply cannot be seriously maintained, in light of these and other recent democratic victories, that homosexuals do not have the ability to protect themselves from discrimination through democratic processes such that extraordinary protection from majoritarian processes is appropriate."

Once Jones decided that "rational basis," the lowest type of scrutiny, would be applied to Nevada's prohibition on allowing same-sex couples to marry, he quickly found several reasons for upholding the differential treatment.

"The protection of the traditional institution of marriage, which is a conceivable basis for the distinction drawn in this case, is a legitimate state interest," he began, adding that if the state recognized same-sex couples' marriages, "it is conceivable that a meaningful percentage of heterosexual persons would cease to value the civil institution as highly as they previously had and hence enter into it less frequently ... because they no longer wish to be associated with the civil institution as redefined."

Notably, Jones began his opinion by looking at the nature of the distinction drawn by Nevada itself.

"Homosexual persons may marry in Nevada, but like heterosexual persons, they may not marry members of the same sex. That is, a homosexual man may marry anyone a heterosexual man may marry, and a homosexual woman may marry anyone a heterosexual woman may marry," he wrote. "Although the State appears to have drawn no distinction at all at first glance, and although the distinction drawn by the State could be characterized as gender-based ... the Court finds that for the purposes of an equal protection challenge, the distinction is definitely sexual-orientation based."

The case was brought by Lambda Legal, whose lead attorney on the case, Tara Borelli, said in a statement, "We will appeal and continue to fight for these loving couples, who are harmed by Nevada's law barring marriage for same-sex couples. By forbidding same-sex couples' access to marriage, the State brands them and their children as second-class citizens."

Their appeal will be to the Ninth Circuit Court of Appeals.