Some Missouri retired judges say they were underpaid based on a 2010 policy change that tied state judges' salaries to their federal counterparts' pay.
The judges' attorneys argued to the state Supreme Court Monday that Missouri owes them back pay and an increase in retirement benefits.
The judges' lawsuit follows similar suits by federal judges.
Federal judges claimed Congress in some years withheld paying them cost-of-living adjustments they were entitled to under a 1989 federal law. That meant Missouri judges also were paid less.
The federal judges won in court and received back pay, so state judges also want compensation.
Assistant Attorney General Robert Presson says the state paid judges properly based on what their federal counterparts were making at the time.
Supreme Court judges didn't indicate when they'll rule.
