My first guess would be not in Hawaii(but then again that must be your best bet too) just call each school and ask. Common sense would tell you that if it's on their application then they are interested in it.
I've actually had conflicting answers on this one; each definition i've seen for law schools fails to designate beyond "Native American," but in some definitions, like the AAMC definition, the term "Native American" denotes Native Hawaiians and Native Alaskans also. Is it perhaps a school-by-school designation?
Thanks