Harold Demsetz sostiene que el medio ambiente es un bien público porque el coste de transacción de perseguir y penalizar la contaminación es demasiado alto: los beneficios de contaminar suelen estar concentrados, mientras las externalidades negativas están dispersas entre una multitud de afectados. Kevin Carson, partiendo de premisas mutualistas (que los lectores habituales de este blog conocerán de memoria) le da la vuelta a la tortilla: la clave no está en que los costes de perseguir y penalizar sean demasiado altos, sino en que los costes de contaminar masivamente son demasiado bajos. De hecho, artificialmente bajos.
If we look at the actual historical record of how tort liability law has dealt with negative externalities like pollution, it’s clear that the state has had a huge effect on shifting the comparative transaction costs of enforcing different kinds of property rights in a particular direction — namely, reducing the costs for large property owners (in particular firms in extractive industries) to enforce their rights against squatters and trespassers, while increasing the costs of small interests enforcing (for example) rights against polluters.
The bare act of large-scale engrossment of vacant land by the early American state, followed by large-scale land grants or grants of preferential access to favored railroad, mining, drilling, timber and ranching interests, is one example.
Another is the changes which American courts made in common law liability rules, as described by Morton Horwitz in “The Transformation of American Law.” The common law of liability was substantially changed in the early decades of the nineteenth century to protect businesses against liability for things that were regarded as a normal part of doing business, even if it resulted in real harms to third parties.
Yet a third example is the twentieth century regulatory state, which preempted common law liability altogether and created safe harbors for those who met its dumbed-down standards. In functional terms, this was a direct continuation of the process Horwitz described. A polluter who meets EPA standards can point to that as a legal defense, even if a plaintiff can marshal good scientific evidence that the pollution caused her significant harm.