The Trump administration sidelined career staffers at the Environmental Protection Agency when weakening pollution rules for new passenger vehicles, according to a federal watchdog report.

The EPA’s inspector general found top political leaders at the agency failed to properly document and consider the concerns of staff experts while unwinding standards for tailpipe emissions set under President Barack Obama. The report, released Tuesday, may provide fresh fodder for the Biden administration to tighten mileage and greenhouse gas standards for new automobiles as part of a broader effort to phase out internal-combustion engines and drastically cut the nation’s climate-warming emissions.

President Biden’s team is in the midst of negotiations with carmakers, autoworkers and environmentalists for new pollution standards for new vehicles, aiming to protect factory jobs and cut emissions. The industry wants generous government incentives for producing cleaner cars, while labor leaders want to stave off job losses during the transition to electric vehicles.