Japan's legal system
Japan's taxation system is but a subsection of Japan's overall legal system. Japan's legal system is quite different from America's in a number of ways.
First, Japan has significantly fewer lawyers than the US. I've heard various reasons for this, including the rationale that because Japan is a "group-oriented society," the Japanese are not as prone to sue each other as the individualistic Americans. That may be so, but I think that because Japan places limits on the number of new lawyers, this makes for a bigger reason.
Japan's legal system is even slower than the American system. Thus, when a conflict arises, parties are more apt to settle out of court because the resulting litigation would simply take too long.
Also, in Japan, business transactions are less dependent on written agreements than they are in America. Oral contracts carry more weight in Japan.
Japanese laws are also more or less national in scope. Although municipalities may pass ordinances, the Japanese Diet is the sole legislative body, so unlike the United States, where various state statutes supplement federal laws, laws in Japan apply uniformly nationwide.
Also, as opposed to the United States, there is no doctrine of strict product liability in Japan. Some Japanese consumer groups, and even American businesses, have been pushing for the adoption of the principle of strict product liability. Some of these American manufacturers believe that the adoption of such liability principles will make it easier for them to export to Japan because product liability might reduce the number of safety tests and other regulations imposed on products.
However, because of strong opposition from Japanese businesses, adoption of the principle of strict product liability has been put on hold.
Finally, Japan's legal system differs fundamentally from America's in that Japan is a civil law nation, like many nations in Continental Europe, while America is a common law nation. That is, Japan's legal system is defined by statues, with little regard for judicial precedents, while America's legal system is defined by its laws and prior court decisions.
However, Japan does have some common law aspects. For example, computer programs were afforded copyright protection in Japan even before the copyright law was amended to provide such protection.