Modern law is supposed to be open, so that anyone can read it. Reencoding laws, for whatever reason, strikes me as being fundamentally undemocratic.
The argument can be made that if legal "code" is taught in schools, then it's no more undemocratic than writing down law, but the chances of that happening seem slim to none.
Another argument is that law is already written in "special" English that most people can't figure out, but I think that having it in English alone is a big step toward having it being readable by almost anyone.
It would be neat to have law written as code and to have AI be able to parse it for you in lay language -- that is, you could ask it questions or pose situations to get a legally-binding answer. But then the question for me is, why don't we just have said AI read the current legalese and parse it?