To quote our Pope Emeritus in the Compendium of the Catechism: “When non-lethal means [of punishment] are sufficient, authority should limit itself to such means because they better correspond to the concrete conditions of the common good, are more in conformity with the dignity of the human person, and do not remove definitively from the guilty party the possibility of reforming himself.”
I hope no-one here is saying this is contrary to the tradition? Yes, in past times the death penalty was freely allowed as a prudential option for legislators, but today it’s not for developed societies that can afford other options–a practical impossibility in earlier times, if order was to be kept. It is still in a sense a prudential decision, of course, but, sorry, the popes have (for Catholics at least) made a large part of that decision already. Now, there was a strain of medieval Catholic piety that thought it good for lay people to voluntarily abstain from offices that administer the death penalty as a free act of mercy. The Church now requires this in some societies. Punishments always serve a number of purposes, which can be somewhat in tension with each other. The death penalty might be best retributively for some serious crimes. But in the light of the justice of the Cross, the justice of strict retribution can easily be outweighed by other factors, even in ways that are morally necessary in some circumstances, which the magisterium has every right to judge.
Another criticism comes from the novelist David Foster Wallace , who in a 1985 paper " Richard Taylor 's Fatalism and the Semantics of Physical Modality" suggests that Taylor reached his conclusion of fatalism only because his argument involved two different and inconsistent notions of impossibility.  Wallace did not reject fatalism per se , as he wrote in his closing passage, "if Taylor and the fatalists want to force upon us a metaphysical conclusion, they must do metaphysics, not semantics. And this seems entirely appropriate."  Willem deVries and Jay Garfield, both of whom were advisers on Wallace’s thesis, expressed regret that Wallace never published his argument.  In 2010, the thesis was, however, published posthumously as Time, Fate, and Language: An Essay on Free Will .