Minnesota could be the latest state—and the first in the Midwest—to adopt California's emissions rules, requiring greater fuel efficiency than federal standards.

Proposed in 2019, tougher emissions rules achieved a major breakthrough this week when an administrative law judge ruled that the Minnesota Pollution Control Agency's rule-making process conformed to state law, removing one potential hurdle to adoption.

Dubbed Clean Cars Minnesota, the new rule would come into effect with the 2025 model year, but Republican lawmakers are working to slow down or halt the rule-making process, according to KARE 11 news.

Minnesota dealerships have opposed stricter emissions rules, claiming they will be saddled with unwanted electric cars. State lawmakers recently pushed for the adoption of a new tax on EVs to replace gas tax revenue.

Advocates, however, are enthusiastic about Clean Cars Minnesota precisely because it will prod automakers to bring more EVs to the state. Current estimates indicate the new emissions rules could eliminate 1 million tons of carbon emissions by 2030, the Sierra Club noted.

Minnesota Tesla Model S owners demonstrate their cars in Urbandale, Iowa, Oct 2014 [KCCI 8 video]

Minnesota Tesla Model S owners demonstrate their cars in Urbandale, Iowa, Oct 2014 [KCCI 8 video]

"For climate action, public health protection, and consumer choice, Minnesota becoming a clean cars state is a significant step with major benefits," Hieu Le, a representative of the Sierra Club's Clean Transportation for All campaign, said in a statement.

A Consumer Reports survey found that most prospective car buyers in Minnesota are interested in electric vehicles, indicating some degree of pent-up demand in the state.

If Clean Cars Minnesota is enacted, Minnesota would be the 15th state (plus the District of Columbia) to follow California's stricter emissions rules.

Meanwhile, California just last week announced a plan for vehicle emissions that includes new EV targets and would go into effect starting in 2026.

The Biden administration is in the middle of several procedural steps required to restore California's right to set its own rules for greenhouse gas emissions, which the Trump administration attempted to strip away.