An environmental group has lost its bid to view documents about a “revolving door” investigation in which a former federal chemical safety official later advocated for his client Chevron Corp. in front of his previous employer.

Public Employees for Environmental Responsibility sought records from the U.S. Environmental Protection Agency’s inspector general office concerning a potential violation of federal “revolving-door” prohibitions by a former chairman and member of the U.S. Chemical Safety and Hazard Investigation Board.