 In addition to the Katrina rulings, on November 19, 2009, Duval ruled that the Army Corps of Engineers was negligent in maintaining flood protection that resulted in significant flooding during Katrina.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.In 2008, Duval assumed senior status.