State attorneys general have been working together to protect their state interests through several lawsuits filed in May. On May 13, a coalition of 24 Republican state attorneys general, led by Nebraska’s Mike Hilgers, filed a lawsuit against a recent Environmental Protection Agency (EPA) rule, “Greenhouse Gas Emissions Standards for Heavy-Duty Vehicles – Phase 3,” which aims to reduce emissions from heavy-duty vehicles starting in 2027. The group argues that these regulations will negatively impact the trucking industry, raise consumer prices, and negatively affect the labor market. The EPA’s rule was finalized in March, and in combination with other federal efforts, it places a major strain on domestic supply chains.

In addition to the EPA rule, Nebraska Attorney General Hilgers is leading a multi-state challenge to California’s emission standards. The California suit challenges a suite of California regulations called Advanced Clean Fleets, which require certain trucking fleet owners and operators to retire internal-combustion trucks and transition to more expensive and less efficient electric trucks. The rule applies to fleets that are headquartered outside of California if they operate within California. Given California’s large population and access to ports for international trade, this regulation will have significant nationwide effects on the supply chain.  Both lawsuits push back on electric vehicle mandates and argue that the Biden administration and California regulators have overstepped their constitutional authority.