The Statuto Albertino
The Statuto Albertino is a decision unique to Sardinia-Piedmont. It cannot be taken once Italy is formed. The decision is an introduction of a constitution, but unlike the similar Liberian decision Constitution for Liberia it doesn't actually change any reforms.
The ingame text: The Albertine Statute was a constitution enacted by the Kingdom of Sardinia-Piedmont, in response to concerning revolutionary activity in the country, on the 4th of march 1848. The Statute formalized the absolute monarchy of Sardinia-Piedmont, and would later be used, although in modified forms, as the basis of the Italian constitution all the way up to 1948