The state Supreme Court expects to issue its long-awaited ruling in a case challenging the state's gay marriage ban on Wednesday, justices announced.

The short notice, posted on the court's Web site Tuesday, gave no indication of how the court might rule.

The 38 plaintiffs in the case — 19 gay and lesbian couples seeking to marry — challenged the constitutionality of the state's 1998 Defense of Marriage Act, which limits marriage to heterosexual couples.

In 2004, judges in King and Thurston counties overturned the law, citing the state constitution's "privileges and immunities" section. The cases were consolidated for Supreme Court review.

In arguments before the Supreme Court in March 2005, plaintiffs' attorneys argued that the gay marriage ban violates a constitutional prohibition against granting privileges to one group of citizens and not another. They also argued the gay marriage ban violates the state's Equal Rights Amendment.

Attorneys defending the marriage law said the state has a rational reason for limiting marriage to heterosexual couples, because the state has an interest in regulating relationships that produce children.