Haw. Rev. Stat. § 235-116
All tax returns and return information required to be filed under this chapter shall be confidential, including any copy of any portion of a federal return that may be attached to a state tax return, or any information reflected in the copy of the federal return. It shall be unlawful for any person, or any officer or employee of the State, including the auditor or the auditor's agent with regard to tax return information obtained pursuant to section 23-5(a), to make known intentionally information imparted by any income tax return or estimate made under sections 235-92, 235-94, 235-95, and 235-97 or wilfully to permit any income tax return or estimate so made or copy thereof to be seen or examined by any person other than the taxpayer or the taxpayer's authorized agent, persons duly authorized by the State in connection with their official duties, the Multistate Tax Commission or the authorized representative thereof, except as otherwise provided by law. Any offense against the foregoing provisions shall be punishable as a class C felony.
HRS § 235-116