Although I'm a slow reader, reading English sentences is fun because I find them more well-structured than those of Japanese.
Mentioning one language is more superior to another always gets political and controversial. So I'd say there's "officially" no functional superiority or inferiority between languages.
Nonetheless, experienced language learners can easily recognize that each language has its own strength and weakness depending on which matter you want to express by that. In my opinion, no other language is more excellent in terms of stating legal matters than English. For example, Japanese legal terms obviously lack sufficient vocabulary. Meanings of legal documents easily get obscure when expressed in Japanese.
Let's take a look at a few examples. The legal term "sekinin(責任)" can stand for two distinct English words, that is, liability and responsibility.
Another term "hosho" is even more confusing. Hosho can be stated in three different spellings in Japanese, which are "保証", "補償" and "保障". And these words would mean assurance, grarantee, warranty, surety, certification, compensation, indemnification, and security!
Maybe you can get by daily conversations where the context can help you, but this ambiguity could be fatal in the legal field where one wording could change the whole meaning of a document.