Whenever a district court finds an offender under eighteen years of age guilty of a crime and commits the offender to the custody of the department of corrections and rehabilitation, the department may transfer the offender to the North Dakota youth correctional center; however, the department shall first transfer the offender to the North Dakota youth correctional center if the offender is under sixteen years of age. The department may allow an offender who is between eighteen years of age and twenty years of age to remain at the North Dakota youth correctional center if the department determines that it is in the best interests of the department and the offender and it is not contrary to safety interests of the other residents or the general public. The department shall transfer an offender who has attained twenty years of age to an adult correctional facility. An offender placed by the department at the North Dakota youth correctional center under this section has all the rights to sentence reduction for good and meritorious conduct and all the pardon and parole rights of an adult committed to the legal and physical custody of the department.