SEATTLE —  A King County (search) Superior Court judge in Seattle (search) ruled Wednesday that gay couples can marry, saying that denying their right to do so would be a violation of their constitutional rights.

"The denial to the plaintiffs of the right to marry constitutes a denial of substantive due process," Judge William L. Downing said in his ruling.

The decision is stayed until the state Supreme Court reviews the case, said Jennifer Pizer, lead counsel for Lambda Legal Defense (search) in the case. The stay means no marriage licenses can be issued until the high court's decision.

"That's totally standard. If it turns out the appellate court disagrees, there would be that much more confusion and difficulty," Pizer said.

"Really the main point is that Judge Downing saw the couples in the court room and he's recognized that they are full and equal citizens of Washington. No more and no less."

Six couples filed the lawsuit in March after they were denied marriage licenses from King County. Two other couples joined the suit later.

A second lawsuit was filed in April by the American Civil Liberties Union (search) on behalf of 11 same-sex couples. The ACLU suit, using similar arguments, contends that the state law violates state and federal constitutions that guarantee equal protection.

Washington is among 38 states with laws defining marriage as a union between a man and a woman. Massachusetts has allowed gay marriage since May. The issue is hotly contested in courts in several other states.