What I found intriguing is that in Japan, the absence of a fair use doctrine forces potential infringers to argue a quite opposite argument.
In the case of fair use, the more transformative the usage is, the more likely for the defendant to win. Therefore, the defendant would argue that the files stored in a database, can be searchable by keywords or other methods, creating an entirely new use for an original work. This tendency is seen in a famous Google Image Search Case, when the court found that "a search engine transforms the image into a pointer directing a user to a source of information [namely the thumbnails]" and found it fair use. Perfect 10, Inc. v. Amazon.com, Inc., 508 F.3d 1146, 1165 (9th Cir. 2007).
However, in Japan, potential infringers are arguing quite the opposite. In Doe v. Shogakukan, 1255 Hanrei-Taimuzu 328 (Tokyo District Court, May 30, 2007), Shogakukan constructed a database to use for licensing pictures. Doe is a photographer who submitted photos to Shogakukan for their magazine. Shogakukan scanned the photos and uploaded them to the database. Doe sued Shogakukan because Shogakukan infringed on Doe's rights of reproduction.
Shogakukan argued, curiously, that it was merely for the purpose of a "back up." It claimed that the database was at the construction stage and it just uploaded the files to avoid deterioration or the loss of the pictures. It further claimed that Shogakukan has no intention of using the uploaded data. For an American lawyer, it may be viewed as denying the transformative nature of its conduct. But that is because of the no fair use doctrine. Here, we can see an interesting difference between a country with a "fair use" doctrine and a country without a "fair use" doctrine.
Tokyo District Court did not buy Shogakukan's argument. Finding that even a reproduction without any intention of using the reproduced copy can constitute a violation of exclusive right of reproduction, and it therefore found a copyright infringement.
Although there is no Japanese case of making a database of briefs, because the briefs are generally not published as in the case of the United States, if Lexis or West publishes briefs of Japanese cases in their database, they are likely to end up in trouble. (Note that in some cases, the court "attaches" a brief to the judgment as a part of its opinion but these are rather rare cases.)