Associated Press: The Iowa Supreme Court says the state's same-sex marriage ban violates the constitutional rights of gay and lesbian couples, making it the third state where gay marriage is legal.

In a unanimous ruling issued Friday, the court upheld a 2007 Polk County District Court judge's ruling that the law was unconstitutional.

In 2005, Lambda Legal, a New York-based gay rights organization, sued on behalf of six gay and lesbian Iowa couples in Polk County who were denied marriage licenses. Some of their children are also listed as plaintiffs.

The case was appealed to the state Supreme Court in 2007, after Polk County District Court Judge Robert Hanson agreed with the plaintiffs and ruled that the ban was unconstitutional.

Hanson's ruling prompted nearly two dozen people to apply for marriage licenses in the county, Iowa's most populous and home to Des Moines. Only one couple, Sean and Tim McQuillan of Ames, managed to get married before Hanson stayed his decision the next day. Their marriage stands, but its validity could depend on whether the state's high court sides with the Polk County judge.

During oral arguments before the Supreme Court in December, Des Moines lawyer Dennis Johnson argued the ban violated his clients' due process and equal protection rights.

"We are suggesting that everybody be able to participate equally in an institution that has existed since the beginning of this state," Johnson said during arguments.

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