The Evidence for Free Trade and Its Background Assumptions: How Well-Established Causal Generalisations Can Be Useless for Policy

In this article, I offer a methodological analysis of the empirical research on the causal effects of trade liberalisation, and assess whether such studies can be of any use for guiding policy prescriptions in real-world economies. The analysis focuses on the mainstream economic research that has been used to support arguments in favour of trade liberalisation during the last decades. Even though there are empirical results that could be taken as valid evidence for a causal connection between free trade and economic gains, none of the existing evidence licences trustworthy inferences about the policy effectiveness of trade liberalisation reforms in real-world cases. There are three aspects of the empirical literature that make it highly problematic for making reliable policy inferences: (a) the criteria used to define the notion of ‘free trade’, (b) the background assumptions embedded in the econometric techniques used for estimating causal effects, and (c) the widespread desire among academic economists to attain scientific results in terms of universally valid generalisations. The analysis exposes a worrisome mismatch between, on the one hand, the research aims and outcomes of scientific economics and, on the other, the kind of evidence that would be useful for guiding actual policy deliberations.