California Gov. Gavin Newsom today issued an executive order requiring the sale of all new passenger vehicles to be zero-emission by 2035. Although the order would require new cars to be zero-emission, it would not prevent Californians from owning gasoline-powered cars or selling them on the used car market. 

Transportation accounts for more than half of the state's carbon emissions, Newsom said. He estimates this executive order would result in a 35% drop in greenhouse gas emissions in the state.   

“This is the most impactful step our state can take to fight climate change,” Newsom said in a televised statement. “For too many decades, we have allowed cars to pollute the air that our children and families breathe. You deserve to have a car that doesn’t give your kids asthma. Our cars shouldn’t make wildfires worse – and create more days filled with smoky air. Cars shouldn’t melt glaciers or raise sea levels threatening our cherished beaches and coastlines.” 

Regarding medium- and heavy-duty vehicles, Newsom mentioned the California Air Resources Board directive issued in June that every new truck sold in California to be zero-emission by 2045 “where possible.” 

As the initiative was put forth by executive order, it is likely to be challenged both legally and politically.
Among many challenges, the Trump administration has previously tried to bar California from setting auto emission standards that are different from the country's standards.