Today's question is about the “twin aims of the Erie rule” in Hanna v. Plumer – that is, the goal of uniformity with a forum state court, in order to avoid “forum shopping” and the “inequitable administration of the laws.” In fact, it's the same question as yesterday: Why did Warren call them the twin aims of the Erie rule? But today's question is based on a different puzzle.
Under the twin aims, a federal court sitting in diversity should use the forum state's statute of limitations, if that is what a forum state court would use. But if the twin aims are about Erie, shouldn't the question be whether the forum state supreme court wants its statute of limitations to be used by federal courts within its borders? The twin aims seem to be about uniformity with a forum state court whatever the forum state supreme court says about the matter. And that doesn't sound like Erie to me. So what makes them the twin ams of Erie?
(Parallel posted on Prawfsblawg.)