Brian Dennis Shannon v. Anthony Newland, Warden

We must decide whether a California prisoner’s petition for writ of habeas corpus is timely when it is filed long after his conviction but shortly after a decision by the California Supreme Court clarifying the state’s criminal law in a way potentially favorable to his federal constitutional claim.

I

In October 1993, Brian Shannon and his girlfriend, Kimberly Stack, began to argue heatedly in the living room of Shannon’s home. Stack was killed by a shot from a handgun that Shannon kept on the premises. Evidence suggested that the couple had been struggling physically at the time of the shooting or shortly before. Shannon was charged with murder and convicted by a jury. The court sentenced him to fifteen years to life on that count, with an additional enhancement of four years for the use of a gun and sixteen months on a weapons possession charge to which Shannon pled nolo contendere.

Shannon appealed his conviction, arguing (among other things) that the trial court had incorrectly instructed the jury. At Shannon’s trial, the jury was instructed on the elements of second-degree murder, which consists, in California, of “the unlawful killing of a human being with malice…