Lambda Legal and the American Civil Liberties Union of Illinois filed a motion for summary judgment Wednesday in Cook County Circuit Court.
They say the judge could rule as soon as Aug. 6, when oral arguments are scheduled on a defense motion to dismiss the lawsuit. The suit was filed last year by couples denied marriage licenses in Cook County.
Two downstate clerks are defending the law after the state attorney general and Cook County state’s attorney refused.
Plaintiffs say the U.S. Supreme Court decision striking down part of a law denying federal benefits to married gay couples creates a new urgency in Illinois, which has civil unions.