Patrick J. Buchanan has this editorial at Human Events, titled "The Greenhouse Effect":
There is another and larger issue here.
It is the question not of what is decided, but of who decides.
Whether Citizen Stevens abhors the death penalty should not matter to Justice Stevens. For if the constitution provides for a death penalty, and capital punishment has been imposed throughout our history, and the form it takes does not violate the ban on cruel and unusual punishment, Stevens' decision should be automatic, no matter his personal beliefs.
What Stevens is signaling, however, is that his altered opinion of the death penalty may cause him to start voting against it -- that is, to substitute his personal view of capital punishment for the decision of the elected leaders who have voted to retain it.