Stockholm experimented with rewarding compliance while punishing free-riders: if you drove at or under the speed limit, you would be entered into a lottery where the prize fund came from fines that speeders paid. The so-called speed camera lottery is the perfect solution for facilitating behavior change on the roads.

Kevin Richardson entered into Volkswagen’s The Fun Theory competition in 2010 with his idea about the speed camera lottery. The concept was so powerful that a year later, Stockholm put it to the test temporarily. When your car passed by a specific crossing, a camera snapped a photo of it and measured its speed. If the driver was above the speed limit, a fine was imposed. However, the money was used to enrich a unique fund – the lottery prize for obedient drivers. If you were not a speeder, you could participate in the lottery, and you had the chance to win some money from those who didn’t follow traffic rules.

It’s simple and brilliant. Sticks and carrots on an entirely new level. It punishes free-riders and rewards behavior benefiting the entire community through a fun game. No wonder Sweden was eager to put the idea to the test. In the trial case, 24,857 cars passed the cameras, and the average speed limit was reduced from 32 km/h to 25 km/h (by 22 percent).