Haw. Rev. Stat. § 660-20: Body to be produced, except when.

The person making the return to a writ of habeas corpus shall bring the body of the person, if in the custody or power of the person making the return, or under the restraint or control of the person making the return, according to the command in the writ, unless prevented by the sickness or infirmity of the person. This shall not prevent the person making the return, if a private person, from demanding in advance actual necessary expenses of travel and transportation.