Haw. Rev. Stat. § 51
That if the governor neither signs nor vetoes a bill within ten days after it is delivered to him it shall become a law without his signature, unless the legislature adjourns sine die prior to the expiration of such ten days.
If any bill shall not be returned by the governor within ten days (Sundays excepted) after it shall have been presented to him, the same shall be a law in like manner as if he had signed it, unless the legislature by their adjournment prevents its return, in which case it shall not be a law.
The first paragraph of this § was taken, by the commission which drafted this act, from the Hawaiian Const. of 1894 (§69), and the second paragraph was added by Congress, from the Federal Const. (Art. 1, §7). The latter giving twelve days, including Sundays, in which to return a bill, probably controls the former, and apparently this was recognized by the legislature in the case of L. 1911, c. 143. In several instances bills have been signed by the governor after the adjournment of the legislature but within ten days after their passage. Referred to in 16 Hawai'i. 245.
HRS § 51