At issue is guidance issued in 2007 that redefined when the Fish and Wildlife Service would protect a species as "endangered" or "threatened." The Endangered Species Act requires protection of any species in danger of extinction throughout all or a significant portion of its range.

Then-Interior Solicitor David Bernhardt issued guidance that recommended agencies focus on plants and animals most at risk in their current locations, rather than throughout their historic range or in other locations where species may be healthy."