Constitutional Transplants and the Mutation Effect

This article is concerned with constitutional transplantation, that is, the borrowing of constitutional institutions and precedents from foreign jurisdictions. It pursues two main goals. First, it argues that the borrowing of constitutional texts can be successful over long periods of time, and that when the transplanted texts fail, this failure is not easily attributable to transplantation alone. Second, it introduces the notion of a mutation effect to the theoretical analyses of judicial transplants. By mutation of precedents, the author means the process of continuing to extend the scope of a holding, regardless of its factual basis, to cover situations not even contemplated in the reasoning that grounded the original decision. The article discusses the mutation effect by using the doctrine of economic emergency, as invoked by the Argentine Supreme Court to justify the government\u27s expropriations of bank deposits. This paper also examines two lines of economic research on legal transplantation. First, the so-called LLSV paper implies that developing countries should transplant corporate and financial law from common law jurisdictions, because this legal family affords stronger protection for investors (e.g., creditors and shareholders) than civil law. Second, the label transplant effect has been used to describe the ineffectiveness of legal transplants that result from insufficient local demand for the transplanted law. By handling the notion of mutation effect the article seeks to qualify the conclusions that could be drawn both from the LLSV and the transplant-effect papers