NEW ORLEANS - Civil rights lawyers in Louisiana say a judge is running a modern-day debtors' prison by sending poor defendants to jail when they can't pay fines and charging them a questionable "extension fee" to avoid jail time.

The Southern Poverty Law Center filed the lawsuit Tuesday against Judge Robert J. Black in Bogalusa and the Bogalusa City Court.

The group is representing four plaintiffs from the small town about 75 miles north of New Orleans.

The group says the judge routinely sends people to jail who can't pay fines for minor traffic or misdemeanor offenses and that the city court is funded on the backs of the poor.

The lawsuit also alleges Black created an "illegal $50 extension fee to buy additional time to pay their monetary penalty."