I would not have thought so, but political scientists Ryan Brutger and Julia Morse have data that says so:
Abstract: Can international courts ever be independent of state influence? If not, how do courts manage the tension between legal principles and political concerns? We address these questions through an analysis of one of the most independent international adjudication mechanisms – dispute settlement at the World Trade Organization (WTO). We find that the ad hoc nature of WTO panels, judicial hierarchy, and panelists’ concern for compliance create a set of incentives that encourage panelists to moderate rulings against the most powerful WTO members. Our analysis shows that WTO dispute settlement panels limit the negative effects of judgements against the United States and the European Union by reducing the scope of such verdicts through the use of judicial economy. We argue that WTO panels use this practice to balance the demands of the law with the concerns of powerful members, which results in a level of judicial restraint on the part of panels and increased prospects for compliance by the US and EU.
...
Our results suggest that WTO panels are responsive to the interests of active and powerful members, specifically the United States and the European Union. When the US or EU is on the losing side of a dispute, panels are more likely to exercise judicial economy, with the probability of judicial economy increasing by 0.39 and 0.31 respectively. Although the lack of significance for the US and EU Complainant variables may seem surprising, this actually fits with our theoretical expectations. If panels are worried about compliance by the US or EU, then they are only likely to moderate their decisions by exercising judicial economy when the US or the EU is on the losing side, rather than in all cases where the US and the EU are participants
This made me think back on my experience at the Appellate Body Secretariat. Did people approach things differently when the U.S/EU was the defending party? After a quick look at my work there, I discovered that none of the cases I worked on had the U.S. or EU as the defending party in the dispute. So I really can't say whether I would have worried about compliance as the paper suggests, or whether, instead, my populist streak would have led to a desire to crack down harder on the WTO's most powerful players.
I am curious to hear what people who have worked on panels involving the U.S./EU as defendants think about this.
