Most recent preferential trade agreements (PTAs) include environmental provisions, as documented on TRENDanalytics. Often trade negotiators do not reinvent the wheel and copy environmental provisions that have been included in earlier PTAs. For example, while the Comprehensive and Progressive Agreement for Trans-Pacific Partnership, signed in 2018, entails a record number of environmental provisions, only two of them, on environmental harmful subsidies, are new. All the other 134 environmental provisions were duplicated from previous PTAs.
While a number of environmental provisions remain rare and are incorporated in just a few PTAs, others are widely popular and are duplicated in more than 100 PTAs. This uncoordinated spread of similar policy models among interdependent countries is often referred to as policy diffusion. Against this background, we are interested why certain environmental provisions diffuse more often than others?
In a new journal article we come up with an explanation for this puzzle. We hypothesise that the initial conditions under which provisions first emerge determine the likelihood of their diffusion. Our results support this hypothesis and indicate that provisions originating from intercontinental agreements diffuse more often than others. Our findings suggest that when more diverse country partners are involved in the introduction of a new provision, this consensus makes it more likely for the provision to be widely accepted in the future and to pollinate external countries across regions.
Overall, our findings indicate that institutional factors matter more for the diffusion of environmental provisions in PTAs than agency factors: The type of PTA and the type or provision in question are more relevant for explaining diffusion than who is inserting a new provision. We did not find evidence that power or environmental credibility of the country that first introduced the provisions has any significant effect on its subsequent diffusion.