Review of scientific
evidence by World Trade Organization (WTO) panels in disputes under the
Agreement on the Application of Sanitary and Phytosanitary Measures (SPS
Agreement) has been a frequent subject of scholarly literature. Despite the
deferential standard of review established by the Appellate Body back in EC –
Hormones and US/Canada – Continued Suspension, panels tend to put WTO member’s
risk assessments to close scrutiny sometimes resembling a de novo review, which
invariably leads to findings of violation. The transposition of the same
standard into the TBT Agreement, however, has produced markedly different
outcomes and secured a win for the respondents on essential issues in the most
recent disputes over Australia’s tobacco plain packaging (TPP) regulation and
the EU’s biofuels regime. This essay identifies the differences in the
approaches adopted by SPS and TBT panels in the evaluation of scientific
evidence and contemplates on the potential causes for such differences.