178. Before the Panel, Mexico challenged the consistency of the US “dolphin-safe” labelling provisions with Articles I:1 and III:4 of the GATT 1994 and Article 2 of the TBT Agreement. Before proceeding to examine the substance of Mexico's claims, the Panel stated that it would determine, as a threshold matter, whether, as contended by Mexico, the measure at issue constitutes a “technical regulation” to which Article 2 of the TBT Agreement applies.

179. In its analysis of this question, the Panel applied what it described as a “three-tier test” and made three intermediate findings. First, the Panel found that the measure at issue applies to an “identifiable” product or group of products, namely, “tuna products” as defined in the DPCIA and Section 216.3 of Title 50 of the United States Code of Federal Regulations. Second, the Panel found that the measure at issue sets out the conditions under which tuna products may be labelled “dolphin-safe” and that it thus establishes “labelling requirements, as they apply to a product, process or production method” within the meaning of Annex 1.1 to the TBT Agreement. Third, the Panel found that the measure at issue establishes “labelling requirements, compliance with which is mandatory”. The United States does not contest the first two intermediate findings made by the Panel. Instead, its appeal focuses on the Panel's finding that the measure at issue establishes labelling requirements “with which compliance is mandatory” and the Panel's conclusion that the US measure therefore constitutes a “technical regulation” within the meaning of Annex 1.1.