To add a bit of context, it’s not universally celebrated. I don’t mean the killing of Mussolini or the fact that there are still fascists or nostalgics, but specifically the disfiguring of the bodies. Even among antifascists, even among partisans, there were those who considered it barbaric. Most famously, Sandro Pertini told the story (he was there, as a partisan) and famously said “I fight the enemy alive”. I think in this perspective, it’s understandable it has not made an official monument.

It’s still a good thing to remind to fascists of where they belong, but it’s not one of the proudest pages of Italian resistance.

Just FYI this is not just an American thing. In Italy for example the President of the republic can cancel or amend sentences too, and it does happen relatively often, although not in the same partisan way as in the US (but that’s also because the president in Italy is a neutral and representative position).

Some example from few years ago when the president graced 33 people (each with a specific articulated motivation) https://www.ilpost.it/2021/12/10/mattarella-grazia-sette-persone-sebastian-oberleteir-heinrich/ (in Italian, but you can translate if you wish).