South Dakota same-sex marriage ban unconstitutional, U.S. judge rules

South Dakota's ban on same-sex marriage violates the right to due process and equal protection guaranteed under the U.S. Constitution, a federal judge ruled on Monday.

Judge Karen Schreier ruled in favour of six same-sex couples who challenged the South Dakota ban on gay marriage and put her decision on hold pending appeals.

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"Plaintiffs have a fundamental right to marry. South Dakota law deprives them of that right solely because they are same-sex couples and without sufficient justification," Schreier said in a 28-page decision.

Schreier's ruling came the same day that the U.S. Supreme Court, which is in the midst of deciding whether to take up the issue of gay marriage, declined to take an early look at a challenge to a Louisiana state ban.

The Supreme Court is still considering whether to take up cases concerning gay marriage bans in Ohio, Michigan, Kentucky and Tennessee, all part of the Cincinnati-based 6th Circuit Court of Appeals ruling that upheld same-sex marriage bans in November.

The 6th Circuit ruling stands in contrast with four other U.S. appeals court circuits that have struck down gay marriage bans, a split that increases the likelihood the U.S. Supreme Court will take up the matter.

South Dakota is under the 8th Circuit U.S. Court of Appeals, which has not ruled on same-sex marriage bans. Schreier cited the lack of an 8th Circuit ruling and a substantial public interest in uniformity and stability in issuing her stay.

South Dakota's attorney general was preparing a statement in response to the ruling.