SDCL § 1-15-21: Receipt and disbursement of inmates' funds.

The Department of Corrections may receive and disburse any funds that may accrue to inmates or juveniles in residence at institutions under jurisdiction of the department. Such disbursement shall be made for the benefit of the inmate or juvenile. However, interest earned on joint accounts may be transferred to a benefit fund from which goods and services may be purchased for use by the institutional population.