By-elections (Italian: elezioni suppletive) are held in Italy whenever a parliamentary seat becomes vacant in either the Chamber of Deputies or the Senate of the Republic.
By-elections were reintroduced by the electoral law of 2017.
The new Italian electoral law approved in 2017 and nicknamed Rosatellum, provides the election of members of Parliament in 232 single-member districts for the Chamber of Deputies and in 116 for the Senate of the Republic.
Whenever a seat of this kind becomes vacant, a by-election is called, and a new representative is elected.
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