Haw. Rev. Stat. § 88-55
Civilian field personnel of the Hawaii national guard are entitled to membership credit for all service performed by them in such capacity since August 1, 1946, upon making application therefor and complying with sections 88-59 and 88-324; provided that by federal law or regulation a payroll deduction has been made for the contribution required to be made into the system by the employee.
Any of the foregoing to the contrary notwithstanding, any civilian field personnel of the Hawaii national guard who elected to become, and who became, a member of the federal retirement system after December 31, 1968, shall not be entitled to membership credit for the period of time the individual was a member of the federal retirement system, nor shall the individual be entitled to any previous membership service credit for any period of service between August 1, 1946, and December 31, 1968, if the individual is entitled to a benefit under the federal retirement system for such period of service.
HRS § 88-55