Migrants and mafia as global public goods

Global public goods, differently from what it might be thought, are quite common in the real world. This work suggests that both the governments' struggle against Mafia and the prevention of immigration can be regarded as global public goods. We assume a federation of jurisdictions with two tiers of Government: the central and the local. Regional utility directly represents the preferences of citizens, since the local governments aim at individualistic utility maximization; central government uses the redistribution of resources among the members of the federation to maximize the social welfare which is given, as usual, by the sum of regional utilities. The Central Government aims at welfare maximization. To get its goal it has to find out the efficient way to fund and provide public goods taking into account not only their particular characteristics but also the fact that, in many circumstances, their production faces increasing cost, which may depend both on the quantity of good produced and on the type (high or low cost) of the producer (which, in this framework, coincides with the jurisdiction). Thus the first issue addressed by the paper concerns the choice between central and local provision. Furthermore, as far as the informational structure is concerned, the centre lacks information concerning the type of each region. Thus, the central government's key informational problem concerns the regional costs and quantities with regard both to the public and the private good. Indeed we assume that the centre can observe the expenditure levels but neither the costs nor the outputs associated with those expenditure levels.