The conclusion of the paper seems questionable to me in an American context, though. Say that A sues B asserting a state-law theory that, it turns out, is preempted by federal law (ERISA preemption, say). Sure, the court ought to apply federal law under the Supremacy Clause of the Constitution. But if the parties don’t raise it, and the court doesn’t raise it on its own initiative, deciding the case on the law as the parties have defined it in their papers, has the court erred? I think not. It’s not clear to me why a treaty obligation to apply international law would or should lead to any different result. The author’s concerns seem really to be a CISG scholar’s concerns rather than a lawyer’s concerns: she worries that non-application of the CISG “deprives the expanding body of
CISG case law from valuable additions, and robs the CISG of visibility in those jurisdictions where it is needed most; where the unwillingness of counsel to engage with it may arise from low levels of CISG litigation in their jurisdiction. It signals to other counsel that they really need not bother to plead the CISG, even where it governs.” In other words, and this is a little tongue in cheek, let’s adopt a rule that maximizes the materials for CISG scholars to write about!

I’m glad you found the post useful and saved yourself both time and money. No permission required to share the link, but thanks for asking. Antonin