Unilateral consumption-based carbon taxes and negative leakage

We investigate the performance of a consumption-based carbon tax – implemented by full border carbon adjustment – as an instrument of unilateral climate damage mitigation in a two-period two-country general equilibrium model with a finite stock of fossil fuel. The implementation of that tax in the first period reduces the first-period emissions in the taxing and non-taxing country (negative within period leakage) if income effects are sufficiently weak. Otherwise, it increases the first-period emissions in both countries (green paradox). That result contrasts with the case of a unilateral production-based carbon tax, in which the leakage rate is always positive and possibly exceeds 100%.