Haw. Rev. Stat. § 198D-6: Regulation of use of trails and accesses.

The department, by rule adopted in accordance with chapter 91, may regulate the use of trails and accesses under the department's jurisdiction. Regulation of the use of trails and accesses shall be established for the following purposes:

(1) To preserve the integrity, condition, naturalness, or beauty of the trails or accesses;

(2) To protect the public safety; or

(3) To restrict or regulate public access to protected or endangered wildlife habitats, except for scientific or educational purposes.