— Aaron Brown (Brown) was charged with persistent prison misbehavior, RCW 9.94.070. The trial court dismissed the charge and declared the statute uncon*59stitutional. The Court of Appeals affirmed. We affirm the result on more narrow grounds.
FACTS
On August 13,1997, Brown, an inmate at the Walla Walla State Correctional Facility, committed a serious infraction: refusing to stand when ordered to do so by a correctional officer to facilitate a search of his cell. WAC 137-28-260(556). Brown had no earned early release credit and was, therefore, charged in Walla Walla Superior Court with persistent prison misbehavior. RCW 9.94.070. At that point, Brown had committed at least 175 serious infractions while incarcerated. The trial judge dismissed the charge, finding “RCW 9.94.070 constitutes an unconstitutional delegation of Legislative authority to the Department of Corrections [DOC] . . . .” Clerk’s Papers at 124. The judge also expressed concern the serious infraction rules adopted by the DOC were not promulgated correctly, noting:
[The statute] provides that the rules be “adopted under RCW 72.09.130.” When you look at the serious infractions, they were passed under RCW 72.01.090 which is a different section .... So we have a statute saying you are supposed to pass it under one section and they actually passed it under something else ....
2 Report of Proceedings at 5.
The State appealed. The Court of Appeals affirmed the trial court’s dismissal of the charge on the ground there were inadequate procedural safeguards to restrain the potential abuse of agency discretion, thereby making the statute unconstitutional. State v. Brown, 95 Wn. App. 952, 960-61, 977 P.2d 1242 (1999). The court also noted, while it was technically correct that the DOC failed to follow the explicit requirement in RCW 9.94.070(2) to promulgate the serious infraction rules under RCW 72.09.130, “the trial court apparently accepted the proposition that the Legislature legislated with reference to the existing rules defining serious infractions.” Brown, 95 Wn. App. at 960. The court *60added, however, “that the problem of procedural safeguards discussed above would be further exacerbated by DOC’s designation of new serious infractions subsequent to the passage of RCW 9.94.070.” Brown, 95 Wn. App. at 960. The Court of Appeals vacated the charge by holding the persistent prison misbehavior statute entirely unconstitutional and declined to rest its decision on the narrow, but recognized, ground that the DOC had failed to promulgate rules under the governing statute, RCW 72.09.130. Brown, 95 Wn. App. at 960-61.
The State petitioned for review, which this court granted.
ANALYSIS
Inmates incarcerated in Washington State prisons are allowed to accumulate “earned early release days” and other privileges for good behavior and good performance while imprisoned. RCW 72.09.130(1). The ability to earn early release credit creates an incentive for inmates to follow internal prison rules—a sentence may be reduced by as much as one-third of the total sentence if the inmate does not accumulate serious infractions. RCW 9.94A.150(1); In re Personal Restraint of Smith, 139 Wn.2d 199, 201-02, 986 P.2d 131 (1999). However, those inmates who fail to comply with the internal prison rules can lose their good time credit. RCW 72.09.130(1) authorizes the DOC to decrease the degree of liberty, to withhold privileges, and to decrease the number of earned early release days for inmates who fail to comply with internal prison rules. Some inmates have no earned early release credits. Brown is one of those inmates.
Maintaining discipline over inmates who have no earned early release credit is of concern to the DOC, in part because these inmates have less reason to obey internal prison rules. In 1995, the Legislature responded to the DOC’s concerns by enacting the persistent prison misbehavior statute, RCW 9.94.070. This statute says in relevant part:
*61(1) An inmate of a state correctional institution . . . 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
RCW 9.94.070 (emphasis added).
As Brown notes, following the enactment of RCW 9.94.070, the DOC did not promulgate its serious infraction rules under RCW 72.09.130 according to the statutory requirements. The DOC’s serious infraction rules remained in its disciplinary code, chapter 137-28 WAC,1 and the DOC simply continued to administer its discipline system under a general grant of powers set out in RCW 72.01.090.2 Brown contends the DOC’s failure to appropriately promulgate the list of infractions that can form the basis of a prosecution under RCW 9.94.070 bars the State from prosecuting him. We agree.
RCW 72.09.130 establishes a system wherein inmates can earn and lose early release days and privileges. The statute states in relevant part:
(1) The department shall adopt, by rule, a system that clearly links an inmate’s behavior and participation in available education and work programs with the receipt or denial of earned early release days and other privileges. The system shall include increases or decreases in the degree of liberty granted the inmate within the programs operated by the department, access to or withholding of privileges available *62within correctional institutions, and recommended increases or decreases in the number of earned early release days that an inmate can earn for good conduct and good performance.
(2) Earned early release days shall be recommended by the department as a reward for accomplishment.
RCW 72.09.130. This statute clearly does not contemplate that the violation of internal prison rules could result in a felony prosecution; by its terms, it deals only with maintaining internal prison discipline by creating a system of incentives for conforming behavior and disincentives for nonconforming behavior. Therefore, the rules were not drafted with the requisite statutory requirements in mind and cannot comply with the requirements of the persistent prison misbehavior statute.
To have the force of law, an administrative regulation must be properly promulgated pursuant to a legislative delegation. Manor v. Nestle Food Co., 131 Wn.2d 439, 445, 932 P.2d 628, 945 P.2d 1119 (1997), cert. denied, 523 U.S. 1102 (1998). Agencies are creatures of law and are required to promulgate regulations pursuant to the statute or statutes authorizing them.3 See Hoffman v. Regence Blue Shield, 140 Wn.2d 121, 125, 991 P.2d 77 (2000). While the DOC is exempt from the Administrative Procedure Act (APA), RCW 34.05.030(1)(c), it must still exercise delegated authority under the restraints of the statutes delegating the authority. Cf. RCW 34.05.570(2)(c) (requiring courts to invalidate regulations passed in violation of statutory rule-making procedures where the APA governs).
The mere fact the DOC had a preexisting list of internal prison rules labeled “serious infractions” is not enough to fulfill the statutory mandate in RCW 9.94.070. The DOC erred by simply applying its list of “serious infractions” already promulgated pursuant to RCW 9.94.070(2) in a different context to give substance to a class C felony. We *63affirm the trial court’s dismissal of the charge against Brown.4
Guy, C.J., and Smith, Madsen, Alexander, and Sanders, JJ., concur.
The record indicates the DOC had been in the process of revising its general prison rules at the time the persistent prison misbehavior statute was promulgated. The DOC adopted that list for use under RCW 9.94.070 without additional procedures.
The DOC “is authorized to make its own rules for the proper execution of its powers. It shall also have the power to adopt rules and regulations for the government of the public institutions placed under its control, and shall therein prescribe, in a maimer consistent with the provisions of this title, the duties of the persons connected with the management of such public institutions.” RCW 72.01.090.
Since the time the charge was filed against Brown, the DOC has put into place new regulations. The adequacy of those regulations is not before this court.
Since this case is resolved on nonconstitutional grounds, we do not reach whether the statute is an unconstitutional delegation of power to the DOC.