Whether a federal habeas court may grant relief because California law arguably entitled Harris to comparative proportionality review.
Holding
No. Federal habeas relief may not rest on a perceived error of state law.
Reasoning
Under 28 U.S.C. § 2241, a federal court may disturb a state-court judgment through habeas corpus only when the prisoner is held in violation of the Constitution, laws, or treaties of the United States. A claimed state-law entitlement to a particular form of appellate review does not itself supply a federal basis for the writ.
Harris relied on earlier California cases, but the California Supreme Court had twice rejected his request for comparative proportionality review without indicating that it was departing from its own precedent. In any event, if California law later evolved to provide such review, the appropriate forum to pursue that state-law issue would be the California courts, not a federal habeas court.