The New Tuna-Dolphin Case

It appears that Mexico is moving ahead with its complaint against U.S. dolphin-safe tuna labeling measures.  Here is the panel request: http://www.worldtradelaw.net/pr/ds381-4(pr).pdf  The specific claims are as follows:

1. Mexican products are not accorded immediately and unconditionally any advantage, favour, privilege or immunity granted to like products of any other Member, contrary to Article I.1 of the GATT 1994;

2. Mexican products are accorded treatment less favourable than like products of US origin, contrary to Article III.4 of the GATT 1994;

3. Mexican products are accorded treatment less favourable than like products of US origin and like products originating in any other country, contrary to Article 2.1 of the TBT Agreement;

4. The measures have the effect of creating unnecessary obstacles to trade, contrary to Article 2.2 of the TBT Agreement;

5. The measures are maintained although their objectives can be addressed in a less trade-restrictive manner, contrary to Article 2.3 of the TBT Agreement; and

6. The measures do not use as their basis an existing international standard, contrary to Article 2.4 of the TBT Agreement.

And, of course, there is sure to be a GATT Article XX defense.

I'm curious to see how the non-discrimination issues are argued.  If I understand correctly, the law is neutral on its face, in the sense that products from all countries are eligible for the dolphin-safe label.  In practice, though, certain countries have not qualified, leading to a disparate impact on these countries.  There are a number of factors the panel could take into account here, and it will be interesting to see where the focus lies.