German cities just got the green light from a high court to start banning some of the 15 million diesel vehicles currently on city streets as part of an effort to cut air pollution specifically caused by diesel engines.

The decision could have far-reaching consequences for the country’s automakers and the diesel technology they promoted for decades as “environmentally friendly.”

Other European countries have also taken measures to reduce the number of diesel-powered cars to reduce nitrogen oxide emissions to E.U.-mandated levels, but diesel technology is nearly synonymous with Germany.

“Limited bans for certain diesel cars are within the law,” the court indicated in its ruling for one way that cities can meet the emissions limits on the emission of nitrogen oxide established by the European Union in 2010.

The court also found that when emissions exceeded allowed limits, banning all vehicles with diesel motors older than 2014 and gasoline engines older than 2001 was the only way for the municipal authorities to ensure air quality.

Learn more @ NPR