Important Notice: New Electoral Systems for the Senate and the Chamber of Deputies

In December 2005, Italy adopted bonus-adjusted proportional representation electoral systems for elections to the Senate and the Chamber of Deputies; in turn, these were replaced by new, mixed electoral systems introduced in October 2017. This page describes the system used for the 1994, 1996 and 2001 elections to the Chamber of Deputies.

An overview of the Chamber electoral system introduced in 2005 is presented here.

The Italian Chamber of Deputies is composed of 630 members. A total of 475 seats are filled in single-member constituencies or colleges (collegi); the remaining 155 seats are distributed by proportional representation (PR). Beginning with the next parliamentary election, due in 2006, Italian citizens residing abroad will elect twelve deputies, and the number of proportional mandates will decrease to 143. Chamber seats are apportioned among twenty-seven electoral districts (circoscrizioni elettorali) according to their population. Generally speaking, these districts follow regional boundaries; however, some of the larger regions are split in two districts (Piemonte, Veneto, Lazio, Campania, Sicilia) or three (Lombardia). Approximately three-quarters of the deputies in each district are elected in single-member colleges; PR is used to choose the remaining one-quarter, except in Valle d'Aosta, which elects one deputy in a single-member constituency.

For the 2001 Chamber election, the distribution of seats by electoral districts was as follows:

Chamber single-member colleges are filled by the plurality or first-past-the-post method, under which the candidate obtaining the largest number of votes in each college is elected. College candidates must be affiliated to at least one party (or party coalition) list presented at the district level for the distribution of proportional seats. Each elector casts two votes in Chamber elections: one for a college candidate, and a second vote for a party list. The votes are cast on separate ballots. Party lists are closed, so electors may not choose individual candidates in or alter the order of such lists.

Since 1993, proportional seats are initially allocated at the national level among party lists that have obtained at least four percent of the valid vote; the apportionment is carried out by means of the largest remainder method of PR. These seats are subsequently distributed at the district level following a complex mathematical procedure, designed to insure that seats are filled in all twenty-six multi-member districts, without changing the nationwide distribution of proportional seats.

Proportional seats are distributed according to the national electoral total (cifra elettorale nazionale) obtained by each qualifying party list, which equals the number of votes obtained by the list on a nationwide basis, minus part of the votes obtained by each of the party's candidates elected in a single-member college. Usually, this subtraction - scorporo in Italian - equals the number of votes obtained by the second-placed college candidate, plus one. However, the subtraction may not be less than twenty-five percent of the valid constituency vote, unless the winning college candidate has obtained a smaller amount, in whose case the scorporo equals the number of votes obtained by the elected candidate. In the event a winning constituency candidate is supported by more than one party list, the subtraction is deducted in proportion to the number of votes obtained by each affiliated list.

However, it should be pointed out that the Italian electoral law does not require that single-member college candidates be affiliated to their respective party lists. As such, a party could have its candidates linked instead to a "decoy" list (lista civetta), a non-existent party list with no chance of reaching the four percent threshold, presented solely to accumulate the votes deducted by scorporo. In this manner, the real party list would suffer no deduction of proportional votes, thus allowing the party to increase its share of list seats. This scheme was extensively used by Italy's two major electoral cartels in the 2001 Chamber election.

The proportional representation procedures introduced in 1993 differ significantly from the electoral system used from 1948 to 1992, under which members of the Chamber of Deputies were elected by a two-tier PR system in multi-member electoral districts, formed by groups of provinces - with the exception of Valle d'Aosta, represented in the Chamber by one member elected by simple majority. District seats were apportioned by dividing the number of votes obtained by each list by the Imperiali quota, calculated by dividing the total number of valid votes cast in the district by the number of deputies to be elected, plus two. Any unallocated seats and unused party list votes at the district level were then collected on a national pool, where the seats were proportionally distributed among party lists with no less than three-hundred thousand votes and at least one multi-member district seat, according to the overall number of unused votes accumulated by each qualifying party list. National pool seats won by a party were then allocated among its district lists. Party lists were open, and voters could cast preferential votes for up to three candidates until 1991, and for a single candidate in 1992.

To illustrate the functioning of the reformed electoral system, the results of the May, 2001 Chamber election in the entire country and the tenth electoral district, formed by the Liguria region (which extends over the Italian Riviera and surrounding areas), are presented here in detail. In the election, the tenth district had fourteen college seats and five proportional seats, for a total of nineteen seats. Five groups contested the single-member colleges in the district, namely L'Ulivo (The Olive Tree); the Casa delle Libertà (House of Freedoms); the Lista Di Pietro (Di Pietro List); Democrazia Europea (European Democracy); and the Pannella-Bonino List. At the same time, the following lists contested the proportional seats in the district:

• Democratici di Sinistra (Democrats of the Left)
• La Margherita (The Daisy)
• Il Girasole (The Sunflower)
• Comunisti Italiani (Italian Communists)
• Rifondazione Comunista (Communist Refoundation)
• Lista Di Pietro
• Democrazia Europea
• Pannella-Bonino
• Forza Italia (Go Italy!)
• Alleanza Nazionale (National Alliance)
• CCD-CDU (Christian Democratic Center-United Christian Democrats)
• Lega Nord (Northern League)
• Nuovo PSI (New Italian Socialist Party)
• Paese Nuovo (New Country)
• Abolizione Scorporo (Abolition of Subtraction)

The Olive Tree coalition was formed by the Democrats of the Left, the Daisy, the Sunflower, and the Italian Communists, while the House of Freedoms included Go Italy!, the National Alliance, the CCD-CDU, the Northern League and the New Italian Socialist Party. La Margherita was an alliance of the Partito Popolare Italiano (PPI; Italian Popular Party), the Democratici (Democrats), Rinnovamento Italiano - Lista Dini (Italian Renewal - Dini List), and the Unione Democratici per l'Europa (Democrats' Union for Europe); Il Girasole was a joint list formed by the Italian Democratic Socialists and the Federation of Greens. Finally, Paese Nuovo and Abolizione Scorporo were decoy lists (liste civetta) set up by the Olive Tree and the House of Freedoms, respectively, to circumvent the application of scorporo.

The list affiliations of L'Ulivo and Casa delle Libertà college candidates in the Liguria electoral district were as follows:

College candidates presented by the Lista di Pietro, Democrazia Europea and the Pannella-Bonino List were linked to their respective party lists.

The first step was the allocation of Liguria's fourteen single-member college seats, detailed below:

College seats were awarded to the group obtaining the largest number of votes in each constituency (shown in bold italic). As indicated, the Olive Tree coalition won in nine colleges, while the House of Freedoms cartel won in five; the remaining groups won no constituency seats.

The next step was the calculation of each list's district electoral total (cifra elettorale circoscrizionale). In Liguria, all the winning college candidates - as well as all the second-place candidates - received at least twenty-five percent of the vote in their respective constituencies: as such, in each constituency an amount equal to the votes obtained by second-place candidates plus one was deducted from the vote total obtained by the list to which the winning college candidate was affiliated. The deductions in each college - the scorporo or subtraction - were as follows:

The district-level aggregation of deductions produced the following results in Liguria:

The described procedure was repeated in each multi-member electoral district. The results from all districts were then aggregated at the national level, in order to proceed with the distribution of Chamber proportional seats.

The nationwide results of the proportional vote in the 2001 Chamber election were as follows:

Five lists, namely the Democratici di Sinistra, La Margherita, Rifondazione Comunista, Forza Italia and Alleanza Nazionale received at least four percent of all valid proportional votes cast, or 1,484,911 votes, and were thus entitled to participate in the proportional distribution of seats at the national level. None of the remaining lists that participated in the election reached the four percent threshold; therefore, these were excluded from the allocation of proportional seats.

In order to distribute the proportional seats, the sum of the electoral totals obtained by the five qualifying lists was divided by the number of seats to be allocated, to obtain the national electoral quota or quoziente elettorale nazionale:

Each qualifying list was then assigned an initial number of seats, equal to the integer division of its national electoral total by the national electoral quota, as shown below:

At this point, the allocation of Chamber proportional seats stood as follows:

However, three of the 155 seats remained to be allocated. The largest remainders were then determined, by sorting them in descending order, as shown below:

Since Forza Italia, Rifondazione Comunista and the Democratici di Sinistra had the three largest remainders, one seat was allocated to each of these lists. This operation completed the allocation of seats at the national level in the following manner:

The proportional mandates were then allocated at the district level, following a three-step process. In the first step, the sum of the electoral totals obtained by the five qualifying lists in a given district was divided by the number of district seats to be allocated, to obtain the district quota or quoziente circoscrizionale).

In the Liguria district, the quota was computed as follows:

Then, for each qualifying list, its district electoral total was divided by the district quota, as shown below:

Each qualifying list was then assigned an initial number of district seats, equal to the integer division of its district electoral total by the district quota:

The allocation of seats by whole quotas was repeated in each multi-member electoral district, with the following results:

The second step was to distribute the sixty unallocated seats according to the largest quota fractions in each electoral district, beginning with the least populated district. The process was continued sequentially in the remaining districts, according to their increasing population rank. Any list that reached its nationwide seat allocation at a given stage had its quota fractions disregarded for subsequent seat distributions, so that it would not be awarded further seats.

In the 2001 Chamber election, the distribution of unallocated seats by the largest quota fractions in Liguria came after seats had already been allocated in Molise, Basilicata, Umbria, Trentino Alto Adige, Friuli Venezia Giulia, Abruzzi, Lombardia 3, Lazio 2, Marche, and Sardegna. At this point, no list had reached its nationwide seat allocation, so all quota fractions were considered for the distribution of the three remaining seats in the district. The fractions were then sorted in descending order, as shown below:

Since the Democratici di Sinistra, Alleanza Nazionale and Forza Italia had the three largest quota fractions, one seat was allocated to each of these lists. As a result, the allocation of district seats in Liguria stood as follows:

The allocation of seats in each multi-member electoral district, first by whole quotas and then by the largest quota fractions, produced the following results:

The last step was to distribute three unallocated seats for Rifondazione Comunista, according to the largest remainders obtained by the list in each electoral district where it had not been allocated any seats, shown below in descending order:

Since Rifondazione Comunista had the three largest unused remainders in Campania 1, Liguria and Veneto 1, one seat was allocated to the list in each of these districts, which completed the distribution of Chamber proportional seats at the district level.

In Liguria, Chamber seats were distributed in the following manner:

As a result, the district received an additional proportional seat. This was also the case in Campania 1 and Veneto 1, where Rifondazione Comunista was awarded seats according to its largest unused remainders. The additional seats in these districts came at the expense of the most populated electoral districts: Puglia and Emilia Romagna lost one and two proportional seats, respectively, in the allocation of seats by the highest quota fraction, due to the fact that all but one of the qualifying lists had already reached their respective nationwide seat totals in prior stages of the process.

Nationwide, the results of the May, 2001 Chamber election were as follows:

As in the Senate election, the single-member constituency system favored the House of Freedoms, which scored a decisive victory in the college races, despite its narrow constituency vote lead over the Olive Tree and its allies. However, the allocation of proportional seats also favored the House of Freedoms, whereas in the Senate election most proportional seats went to the Olive Tree. This difference resulted from the overwhelming lead secured by the House of Freedoms in the Chamber proportional vote, combined with the fact that the Democratici di Sinistra and La Margherita accumulated significantly larger deductions than Forza Italia or Alleanza Nazionale: although both the House of Freedoms and the Olive Tree had a large number of constituency candidates linked to decoy lists, the former had far more decoy list-affiliated college candidates (427) than the latter (235). As a result, the application of scorporo in the Chamber election actually worked in favor of the House of Freedoms, despite its large college seat lead.

Incidentally, the House of Freedoms decoy list scheme resulted in one unexpected complication: Forza Italia did not have enough candidates to fill all its proportional mandates. Consequently, a total of twelve list seats have remained vacant since the election was held.

Finally, it should be pointed out that while the four percent nationwide threshold reduced to five the number of lists which received proportional seats, the coalition deals within both the House of Freedoms and the Olive Tree allowed the smaller parties affiliated to these cartels to win Chamber seats in the single-member colleges - seats they would have had practically no chance of winning by themselves. In this manner, the smaller parties managed to get around the four percent threshold, securing parliamentary representation in rough proportion to their voting strength. In fact, despite the introduction of plurality voting in Italian parliamentary elections, the political party system remains as fragmented as ever.

Copyright © 2003-2018 Manuel Álvarez-Rivera. All Rights Reserved.
Last update: March 4, 2018.