Today, the Ninth Circuit issued its Opinion in City & County of San Francisco v. US Department of Transportation, holding the City may not proceed against the Secretary of Transportation and the Pipeline and Hazardous Materials Safety Administration in its case arising from the 2010 San Bruno explosion that killed eight people and leveled an entire neighborhood. The City sought mandamus relief alleging the agencies unlawfully withheld deciding whether California’s Public Utility Commission adequately enforced federal pipeline safety standards and arbitrarily and capriciously approved the PUC’s certification and funding. This case could have broad implications for other public entities trying to force the federal government to enforce safety standards where there is no clear violation of a law or regulation, but merely “troubling allegations” about an agency’s approach to its oversight role.