The Californian Low Emission Vehicles (LEV) Program[L’expérience californienne des quotas de voitures propres]

California can be regarded as a kind of laboratory of the public policies aiming at reducing air pollution, in particular the pollution produced by road traffic, because it is generally in California that these policies are invented and applied in first. Among the Californian policies to fight against automobile pollution, a central place is granted to the exhaust emission standards imposed to the manufacturers. But, whereas the first standards were universal standards similar to those currently into force in Europe, the new standard is an average standard calculated on the whole of the sales of each manufacturer. While bringing more flexibility than the preceding one, this approach makes it possible to lay down more ambitious objectives. To achieve an increasingly stringent average standard each year, the LEV program (for Low Vehicles Emission) proceeds in three stages: (i) it defines categories of vehicles according to increasingly stringent emission standards, (ii) it imposes a mechanism to force the manufacturers and importers in California to modify the set of their sales by gradually introducing increasing proportions of vehicles of the cleanest categories, with the option of marketable credits for complying with or improving on the standards, and (iii) it requires that a given percentage of vehicles be vehicles of the ZEV category, i.e., Zero Emission Vehicles. Very dissuasive penalties are imposed to the manufacturers who do not comply with the average standard. This system, introduced in 1991 and imposed since 1994, was regularly adapted since to take account of economic realities but also technical progress. As for the preceding policies, the American manufacturers subjected themselves there with strong reserves and the Japanese manufacturers played the "first of the class". As with any path breaking policy, the Californian experiment with average standards knew some stammerings, thus the premature will to introduce electric vehicles. But the system functioned well since without slowing down the rhythm of reinforcement of the average standard, arrangements were made to make it possible to substitute other more economic technical solutions.