MEMORANDUM **

California state prisoner Joseph John Etcheverry appeals pro se from the district court’s judgment denying his 28 U.S.C. § 2254 petition. We have jurisdiction pursuant to 28 U.S.C. § 2253, and we affirm.

As a threshold matter, we reject as foreclosed the government’s contention that we lack jurisdiction over this appeal because a certificate of appealability (“COA”) is required. As the district court *279correctly determined, a COA is not necessary where, as here, a state prisoner challenges an administrative decision regarding the execution of his sentence. White v. Lambert, 370 F.3d 1002, 1010 (9th Cir. 2004).

Etcheverry contends that he has a protected liberty interest in the accrual of credits based on his participation in the Inmate Work Training Incentive Program, and that his equal protection and due process rights have been violated by the statutorily-mandated 15-percent cap on work credits he may earn towards his sentence pursuant to California Penal Code § 2933.1(a). On review of the record, we conclude that the decision of the state courts in this case was not contrary to, or an unreasonable application of, clearly established United States Supreme Court authority. See 28 U.S.C. § 2254(d). We reject as foreclosed Etcheverry’s contention that he has a protected liberty interest in the accrual of work credits. See Kalka v. Vasquez, 867 F.2d 546, 547 (9th Cir. 1989); Toussaint v. McCarthy, 801 F.2d 1080, 1094-95 (9th Cir. 1986). Accordingly, Etcheverry’s due process claim fails. See McLean v. Crabtree, 173 F.3d 1176, 1184 (9th Cir. 1999). With respect to Eteheverry’s equal protection claim, we agree with the district court that the state’s interests in treating violent felons more harshly and ensuring public safety provide a rational basis for California’s requirement that Etcheverry, who was convicted of voluntary manslaughter, serve at least 85 percent of his sentence. See Kalka, 867 F.2d at 547.1

Etcheverry’s estoppel contention does not state a violation of federal law and is thus not cognizable in these proceedings. See Lewis v. Jeffers, 497 U.S. 764, 780, 110 S.Ct. 3092, 111 L.Ed.2d 606 (1990) (“[Federal habeas corpus relief does not lie for errors of state law.”).

Finally, we decline to address claims Etcheverry has raised for the first time on appeal, including his contention regarding his entitlement to good-conduct credits. See Allen v. Ornoski, 435 F.3d 946, 960 (9th Cir.), cert. denied, 546 U.S. 1136, 126 S.Ct. 1140, 163 L.Ed.2d 944 (2006); see also 28 U.S.C. § 2254(b)(1)(A).

AFFIRMED.