Haw. Rev. Stat. § 553A-13: Powers of custodian.

(a) A custodian, acting in a custodial capacity, has all the rights, powers, and authority over custodial property that unmarried adult owners have over their own property, but a custodian may exercise those rights, powers, and authority in that capacity only.

(b) This section does not relieve a custodian from liability for breach of section 553A-12.