This paper explores the possibility of an alternative take on the current understanding of the GATT national treatment obligation, especially in the assessment of the possible discriminatory impact of a carbon tax. The traditional legal standard, when applied to an import-adjusted carbon tax measure, may result in a finding of discrimination, despite there being sound economic rationale underlying such a measure. It is proposed that during the analysis of discrimination, comparison between products should also account for emission footprints. Furthermore, to assess the discriminatory impact of a carbon tax, one should not only take into account the tax burden imposed on products, but also the level of pre-existing distortion in the market. This paper finds that while such an alternative approach may be promising, it can, in case of inadequate forethought, run into problems.