Hawaii Revised Statutes Division 1. Government § 231-40.5

(a) Notwithstanding any other law to the contrary limiting the time for assessment of any tax, if a taxpayer omits an amount of:

properly includable therein that is in excess of twenty-five per cent of the amount stated in the return, the tax may be assessed or a proceeding in court with respect to the tax without assessment may be begun without assessment, at any time within six years after the return was filed.

(b) In determining any amount omitted, there shall not be taken into account any amount that is stated in the return if such amount is disclosed in the return or in a statement attached to the return in a manner adequate to apprise the department of taxation of the nature and amount of such item.

(c) This section shall be construed in accordance with regulations and judicial interpretations given to section 6501 of the Internal Revenue Code.