Scorporo was in force for elections to the bicameral Parliament of Italy based on Law 277/1993 from 1993 to 2005. Under this system, members could be elected in two ways:
Approximately 25% of elected members were elected on list basis based on the proportion of the votes received by the party, with the exclusion of a proportion of any first-placed winner's votes.
The system was subject to the following specific rules for each chamber:
Senate
List seats were calculated at the regional level.
All votes for winning candidates were excluded from the list allocation.
No threshold was applied for list seats.
The SMD vote and the list vote were linked, limiting the use of decoy lists.
The list seats were calculated at the national level.
The number of SMD winner's votes excluded from the list vote was equal to the second place candidate's vote total +1. This represented the number of votes needed to elect the winner in the SMD.
A 4% threshold was established for parties to qualify for the list seats.
The local vote and list vote were not tied to each other, thereby providing an incentive for decoy lists.
In the 2001 Italian general election, one of the two main coalitions, linked many of their constituency candidates to a decoy list for the proportional component, under the name Abolizione Scorporo. This list was not designed to win proportional seats, but only to soak up constituency votes for House of Freedoms, enabling them to win a larger share of the proportional list seats than they would be entitled to if all candidates were linked other House of Freedoms parties. This intentionally undermined the compensatory nature of the electoral system. As a defensive move, the other coalition, The Olive Tree, created their own decoy list under the name Paese Nuovo. The decoy lists were extremely successful. Between them, candidates linked to the decoy lists won 360 of the 475 constituency seats, more than half of the total of 630 seats in the Chamber of Deputies. Meanwhile, the decoy lists won a combined total of less than 0.2% of the proportional part of the vote. For the two main coalitions, their vote totals in the proportional component were essentially unaffected by the constituency votes, enabling them to win far more proportional seats than the system was designed for. In the case of Forza Italia, the tactic was so successful that it did not have enough candidates in the proportional component, and its list exhausted before it could be awarded all the seats it had won, ultimately missing out on 12 additional seats. This was facilitated by the fact that this particular scorporo system allowed the single-member constituency vote and the proportional list vote not to be linked. Decoy lists are a common issue in all compensatory and pseudo-compensatory systems, and this was not a unique problem for scorporo.
Abolition
Due to Silvio Berlusconi's opposition to the system, Italy reverted to list semi-proportional representation in 2005. In 2018, parallel voting was brought back.
Use in Hungary
The compensatory tier of the National Assembly of Hungary is allocated to parties crossing a national 5% threshold based on losing candidates' votes in the first round of single district voting. However, each party's totals are further augmented by "any wasted" votes from the regional list-tier elections.
Proportional systems
Several systems using regional list proportional representation contain a compensatory element similar to scorporo for wasted votes at the district or regional level. Because list PR systems may have more than one candidate elected in a district, typically these systems use "wasted votes" rather than the votes of losing candidates. Countries that make use of such tiers are:
Hungary
Austria, which does not use a fixed number of compensatory seats but does allocate votes pertaining to unawarded to fractional seats to its regional and then to a national tier.
Germany proposed a similar compensatory to augment its proposed regionalized MMP as part of its 2009 electoral reform. However, the entire electoral reform law was ruled unconstitutional for other reasons.
