https://arstechnica.com/tech-policy/2021/04/trump-epa-sidelined-its-own-scientists-when-rewriting-fuel-economy-rules/

The Trump administration effectively muffled scientific staffers at the Environmental Protection Agency when it rewrote automobile pollution rules, the agency’s watchdog said.

When drafting fuel economy and greenhouse gas pollution rules for cars and light trucks, former EPA Administrator Scott Pruitt decided to cede various EPA duties to the National Highway Transportation Safety Administration in what is typically a collaborative process, the independent inspector general said in a report released yesterday. Though Pruitt signed the final report for the EPA, he allowed NHTSA staff to write a significant portion of the rule and to complete all modeling and analysis for both agencies.