https://arstechnica.com/tech-policy/2019/09/the-fight-over-fuel-economy-rules-is-getting-messy/

Legal wrangling among the federal government, the state of California, and four automakers who—oddly—are asking for more stringent regulations got even more knotty this month, when the Department of Justice reportedly launched an antitrust probe into companies that struck a deal with California climate regulators.

Now some members of Congress are urging an independent investigation of the investigation, amid suspicions that the probe is an attempt to punish the automakers—and California—for parting ways with federal policy on fuel economy.