Wow, interesting question I never thought about neighbor islands.
I just looked up the FAQ for Federal Court and in Hawaii:
Jurors get mileage to/from the airport, but nothing about the plane fare to/from Oahu, which can be up to $200/RT with nothing said about reimbursement, and take up to a hour one way. No ferries anymore.
If you’re just showing up for jury selection, you get nothing.
Jurors are put up in hotel during the weekdays and expected to return home on the weekends. So another $200 if the trial lasts more than a week.
http://www.hid.uscourts.gov/dsp_FAQ.cfm?catid=7&SNPID=26&SNMID=27#
Thanks for the question!