Mattarella promulgates the new electoral law, the Melonellum is law.

President of the Republic Sergio Mattarella today promulgated the new electoral law, which was definitively approved yesterday by the Chamber of Deputies. The measure, titled "Provisions regarding the elections of the Chamber of Deputies and the Senate of the Republic," sets the rules for the renewal of the two Chambers. The signature from the Quirinal Palace concludes the parliamentary process and makes the text effective.

The new electoral law was published this evening in the Official Gazette, with its entry into force set for next October 24. Only then will the new rules replace the Rosatellum and become the system for electing the Chamber and Senate. The measure, desired by the center-right majority, abandons single-member constituencies and returns to a proportional system with a governability bonus.

The new electoral law, dubbed "Melonellum" by the opposition and "Stabilicum" by the government, stems from the desire of the center-right majority to change the rules of the electoral game. The previous system, the Rosatellum, had been in effect since 2017 and featured a proportional part and a majoritarian part with single-member constituencies. The debate over a reform continued for months, with the majority's stated goal of ensuring greater government stability.

The legislative process concluded yesterday with the final vote in the Chamber of Deputies, where the text was approved with 227 yes votes. The law introduces a governability bonus that is triggered if a list or a coalition reaches at least 42% of valid votes in both Chambers, awarding 70 additional deputies and 35 additional senators. The thresholds of 3% for lists and 10% for coalitions remain. Voters will be able to express preferences, but with the top candidates blocked, and coalitions must indicate their prime ministerial candidate before the vote.