Here is a great contextual example of government intervention! Paris has announced plans to ban private cars from small central areas of the city from 2024.

This is only the second zone of its type in a major European city — after Madrid. The plan is expected to cut around half of daily car journeys through the core area shown. The ban aims to decrease congestion and improve air quality (reduce external costs) in the city ahead of the 2024 Paris Olympics.

On the surface, this appears quite a radical move. It can certainly be contrasted with the approach in London to establish a congestion charge and latterly a low-emissions charge for vehicles entering the designated areas.

Can you think of some of the possible benefits and costs from a private car ban as a form of government intervention? The ruling will only be for private vehicles - some commercial traffic such as taxis may be less impacted. Enforcement will come from cameras randomly sampling the car registration plates of vehicles leaving the zone with fines for cars breaking the law.

Berlin may be nudging towards something similar - with a car limiting scheme