[JURIST] The US Court of Appeals for the Ninth Circuit [official website] on Wednesday upheld [opinion, PDF] an approval by the Environmental Protection Agency (EPA) [official website] of caps on motor vehicle emissions in California. The court held that no abuse of discretion had occurred, citing the broad discretion which must be afforded to a government agency’s interpretations of its own regulations as its reason for upholding the EPA’s decision. A coalition of environmental groups, including the National Resource Defense…