Within the ninety-day period preceding a prisoner having served one-fourth of his sentence, the board, either acting in a three-member panel or meeting as a full board, shall review the case, regardless of whether or not any application has been made therefor, for the purpose of determining whether or not such prisoner is entitled to any of the benefits provided for in this chapter; provided, that in cases of prisoners in confinement due to convictions for nonviolent crimes, an administrative hearing officer may be appointed by the director to review the case who must submit to the full board written findings of fact and recommendations which shall be the basis for a determination by the board. Upon an affirmative determination, the prisoner must be granted a provisional parole or parole. Upon a negative determination, the prisoner’s case shall be reviewed every twelve months thereafter for the purpose of such determination.