Update: Had Ann Dunham been a bit younger... Obama Sr. could have hit the slammer for 20 years:
Hawaii § 707-730 | First-degree sexual assault to knowingly engage in sexual penetration (1) with someone under age 14 or (2) with someone between age 14 and 16 when the offender is more than five years older. | An indeterminate term of 20 years in prison |