Latest in Regulation and Emissions

About Regulation and Emissions

Few things shape a new car as much as the rules it has to pass. Emissions limits decide which engines live and die, fuel-economy formulas reward some body styles and punish others, and trade policy can move a factory across a border. Automakers plan products years ahead, so every shift in Washington, Brussels or Beijing ripples through showrooms long after the press conference ends. This page tracks those rules and the industry's constant effort to influence, adapt to or outlast them.

The story starts with smog. Los Angeles air drove California to regulate tailpipes in the 1960s, the federal Clean Air Act and the Environmental Protection Agency followed in 1970, and the catalytic converter became standard equipment in the mid-1970s. The oil shocks of that decade brought Corporate Average Fuel Economy rules, which helped push buyers toward trucks and SUVs that faced looser targets. Europe's Euro emissions stages and its long love of diesel ran into a wall in 2015, when Volkswagen's defeat-device scandal exposed cars that cheated their tests.

Recent years have been a policy pendulum. Governments set aggressive dates for ending new combustion-car sales, then began revisiting them as electric-car demand grew more slowly than hoped. In the United States, emissions rules, EV tax credits and California's special authority have been rolled back and fought over in court, while tariffs on imported vehicles and parts have rattled automakers, suppliers and neighboring countries alike. China's export surge of low-priced EVs has pushed Europe and North America into protective trade measures of their own.

The stories collected here include rulemakings, lawsuits, tariff announcements, compliance credits, emissions recalls and the industry lobbying around them. It is dry material on the surface, but it explains why the car someone wants may cost more, arrive later or never come at all. The rules also explain stranger things, such as why so many compact cars vanished, why small crossovers carry turbocharged three- and four-cylinder engines, and why the same model can differ between the American and European versions.