text: France, Paris having heavy smog decided to have a partial ban on driving making even numbered license plates not drive or fear a fine. Congestion went down after the experiment. What was to blame for the smog was the Diesel fuel being used in most cars because of the fact that a tax policy favors diesel fuel over gasoline. Paris having more smog than the typical capital had a decrease in congestion and the citiy after enormous victory decided to go at it again and do odd numbered license cars.