(1) Except as provided in subsection (2) of this section, the sentence of a prisoner confined in a county jail facility for a felony, gross misdemeanor, or misdemeanor conviction may be reduced by earned release credits in accordance with procedures that shall be developed and promulgated by the correctional agency having jurisdiction. The earned early release time shall be for good behavior and good performance as determined by the correctional agency having jurisdiction. Any program established pursuant to this section shall allow an offender to earn early release credits for presentence incarceration. The correctional agency shall not credit the offender with earned early release credits in advance of the offender actually earning the credits. In the case of an offender convicted of a serious violent offense or a sex offense that is a class A felony committed on or after July 1, 1990, the aggregate earned early release time may not exceed fifteen percent of the sentence. In no other case may the aggregate earned early release time exceed one-third of the total sentence.
(2) An offender serving a term of confinement imposed under RCW
9.94A.670(5)(a) is not eligible for earned release credits under this section.
(3) If an offender is transferred from a county jail to the department, the administrator of a county jail facility shall certify to the department the amount of time spent in custody at the facility and the number of days of early release credits lost or not earned.