As transnationalism becomes more prominent, comparative law is burgeoning. In one area of American law, however, it has met a formidable challenge: civil procedure. Comparative civil procedure has been relatively slow to find its way into American law-school classrooms, legislation, and judicial opinions.

There are many reasons why, but one reason is American exceptionalism. Though there is a vast difference between common law and civil law jurisdictions, American procedure is very different even from its common law kin. As I and others have stated previously, American exceptionalism is a major obstacle to the benefits of comparative study and to potential reform in the field of civil procedure.

This may be changing, however. Certain features of American procedure historically considered exceptionalist appear to be trending toward their foreign counterparts. These trends, should they continue, may make comparative study, and perhaps even harmonization, easier. They also, however, pose new challenges to the coherence of our own American system.

Pleading is a particularly useful example. It is a prominent feature of American civil procedure that has long been exceptional. Unlike civil law countries, which require detailed fact pleading and often evidentiary support at the outset, and unlike even most common law traditions that also require some fact pleading, Rule 8 requires only “a short and plain statement of the claim showing that the pleader is entitled to relief,” a formula that has traditionally focused on notice rather than facts. This conception of pleading is unlike any other in the world.

But exceptionalism in American pleading may be waning, at least in discrete areas. Congress has begun to experiment with imposing heightened pleading requirements in, for example, the Private Securities Litigation Reform Act of 1995. Similarly, but perhaps more dramatically, the Supreme Court in Bell Atlantic Corp. v. Twombly and Ashcroft v. Iqbal recently imposed a transsubstantive “plausibility” standard that depends upon factual sufficiency, eliminating the more liberal notice-pleading standard that the Court had endorsed since 1957.