The Supreme Court refused to retroactively apply its Ring vs. Arizona decision which held that juries, not judges, must decide facts used to determine the death penalty, to more than 100 similar cases pending around the country:

The 5-4 decision spares at least four states from having to decide whether to spend millions of dollars for new sentencing hearings or consent to prison sentences for the convicted killers. It was issued on the two-year anniversary of the Supreme Court's ruling that the constitutional right to a trial by jury means that jurors should weigh factors that determine whether a particular killing merits death or life in prison. Justices said in the follow-up decision that the 2002 ruling does not apply retroactively.

....The ultimate question for the Supreme Court, which does not automatically make its rulings retroactive, was whether this one involved "watershed" rules. It did not, said Justice Antonin Scalia, writing for the court. "The right to jury trial is fundamental to our system of criminal procedure, and states are bound to enforce the Sixth Amendment's guarantees as we interpret them," Scalia wrote.

It does not follow, however, that when a defendant has had a full trial and has lost the appeal of his conviction "he may nonetheless continue to litigate his claims indefinitely on hopes that we will one day have a change of heart," Scalia wrote.

The dissenters: John Paul Stevens, David H. Souter, Ruth Bader Ginsburg and Stephen Breyer. Ginsburg authored the 2002 Ring decision. The opinion (html) is here. (Schriro v. Summerlin).

Update: The decision could spell trouble for Mumia. We received this by email from Karl at Capital Defense Weekly: