Justice Scalia basically orchestrated the Ring decision that invalidated death penalty statutes across the nation by requiring that juries make the call on death rather than judges. Today, however, he issued an opinion which let 100 other death row inmates go to the gallows because Ring was a "new rule" of Constitutional law which was "procedural". So 100 men will die from sentences that could not have been imposed today in the way that they were, or if they had successfully raised the issue in their own appeals.
The same jury v. judge rule came up in another case, out of Washington, also 5-4, in which Scalia, writing for a majority, invalidated a sentencing scheme remarkably similar to the federal sentencing guidelines. This has imposed harsh mandatory minimum sentences on thousands, if not tens of thousands or hundreds of thousandsd of people, often grossly inappropriate to the crime committed and often coercing innocent people to plea guilty for fear that the guideline sentence would apply. Many federal judges have refused to take criminal cases at all as a result and the Court has protested to Congress for legislative action.
This is exceptional news because while the Supreme Court often rules on death penalty case issues, those cases often do nothing to address injustices in cases involving less than the death penalty. But, this ruling has the potential to be broadly applicable and end deep rooted flaws in the criminal justice system for them.
Scalia is an odd man with weird theories, but his newfound concern for the right to trial by jury has had a good effect on the law, although this is cold comfort to the 100 men who die because that revelation came too late.