He was raised in Houma, the seat of Terrebonne Parish, where his father operated a successful insurance business and was prominent in community affairs.

He practiced law from 1966 to 1994 in Houma eventually becoming a senior partner of Duval, Funderburk, Sundbery and Lovell, LP.

Duval's opinion was unanimously reversed by the Fifth Circuit Court of Appeals in New Orleans on April 13, 2005.

The literature, though it doesn't specifically name him, labels U.S. District Judge Stanwood Duval II, as a 'left-wing' jurist.

"[9] Most significantly, Duval presided over the litigation arising out of the Hurricane Katrina and the failure of the levee system.

The court consolidated over 1,200 cases comprising hundred of thousands of claims and systematically adjudicated the lawsuits.

He extended the time that hurricane evacuees could continue receiving taxpayer-funded hotel stays.

On March 3, 2012, the Fifth Circuit Court of Appeals upheld Duval's ruling, agreeing that the Corps had failed to maintain the Mississippi River-Gulf Outlet.