Porcellum

The Italian electoral law of 2015, better known as Italicum, a name given to it in 2014 by the Democratic Party secretary and subsequently head of government Matteo Renzi, who was its main proponent (until the end of January 2015 with the support of Forza Italia's leader Silvio Berlusconi) provides for a two-round system based on party-list proportional representation (the former being ruled out as unconstitutional), corrected by a majority bonus and a 3% election threshold. Candidates run for election in 100 multi-member constituencies with open lists, except for a single candidate chosen by each party who is the first to be elected.

The law, which came into force on 1 July 2016, regulates the election of the Chamber of Deputies, replacing the previous electoral law of 2005, modified by the Constitutional Court in December 2013 after judging it partly unconstitutional.

The law was written under the assumption that, by the time it came into force, the upper house would have become an indirectly-elected body representing regions, with greatly reduced powers, thus making a reform of its electoral system unnecessary. The upper-house reform, rejected in the 4 December 2016 Constitutional Referendum, was originally assumed to be adopted without a Referendum by 1 July 2016.

It is the first electoral law, which even if it was approved by the Italian Parliament, has never been used in a general election.

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