Haw. Rev. Stat. § 134-3.5: Disclosure for firearm permit and registration purposes.

A health care provider or public health authority shall disclose health information, including protected health care information, relating to an individual's mental health history, to the appropriate county chief of police in response to a request for the information from the chief of police; provided that:

(1) The information shall be used only for the purpose of evaluating the individual's fitness to acquire or own a firearm; and

(2) The individual has signed a waiver permitting release of the health information for that purpose.