(1) An inmate of a state correctional institution who is serving a sentence for an offense committed on or after August 1, 1995, commits the crime of persistent prison misbehavior if the inmate knowingly commits a serious infraction, that does not constitute a class A or class B felony, after losing all potential earned early release time credit.

(2) "Serious infraction" means misconduct that has been designated as a serious infraction by department of corrections rules adopted under RCW 72.09.130.

(3) "State correctional institution" has the same meaning as in RCW 9.94.049.

(4) The crime of persistent prison misbehavior is a class C felony punishable as provided in RCW 9A.20.021. The sentence imposed for this crime must be served consecutive to any sentence being served at the time the crime is committed.