Majority bonus system

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The majority bonus and majority jackpot systems (MBS/MJS) are two methods of semi-proportional representation used in some European countries. These mixed systems give extra seats in a legislature to some parties, with the aim of providing government stability.

It is currently used in Greece,^[a] Armenia, San Marino, French Polynesia and formerly in Italy from 2006 to 2013.^{[citation needed]} In Argentina, it is used in the Chamber of Deputies of Santa Fe, Chubut, and Entre Ríos.^{[citation needed]}

Benito Mussolini was the first politician to enact a law to give automatic seats to the winning party and ensured his victory in the 1924 Italian general election. A modified version of the system was reintroduced for the 1953 Italian general election, in which any parliamentary coalition winning an absolute majority of votes would be awarded two-thirds of the seats in Parliament. The Christian Democracy-led coalition fell narrowly short of this majority in the election, and the system was abolished before the 1958 election. The majority bonus system was used in Italian local elections in the 1950s and was reintroduced for local elections in 1993 and national ones in 2006 to replace the scorporo mixed system. In the 2013 Italian general election, the Democratic Party won 292 seats in the House using its 8,644,523 votes and so needed 29,604 preferences to obtain a seat. Its major opponent, The People of Freedom, won 97 seats with 7,332,972 votes and so needed 75,597 votes for a single seat. Effectively, the system in use in Italy from 2006 until 2013, which assigned the jackpot regardless of the percentage of vote achieved by the largest party, was judged as unconstitutional by the Italian Constitutional Court.^[1][2] After a proposed modification involving a run-off vote (between the top two alliances) was also struck down by the court, parallel voting was adopted for the 2018 Italian general election.^[3]

There are two main majority-bonus systems:

• The bonus system adds a certain fixed number of additional seats to the winning party or alliance. In the Greek Parliament, where it is sometimes called reinforced proportionality, a sixth of the assembly seats are reserved as extra seats for the winning party. In the Sicilian Regional Assembly, a tenth of the assembly seats are granted to the winning coalition on top of those allocated proportionally. The size of majority bonuses may vary greatly, from as low as a few seats to up to 50%. In case of a bonus of 50%, the party also received their proportional share of the other 50% seats, which make a supermajority almost certain.
• The jackpot system ensures the winning party or alliance ends up with at least a certain fixed number of seats in total, by granting it however many additional seats are needed. In the Sanmarinese Parliament, the majority alliance is given 35 out of 60 seats.^[4] A majority jackpot system can be seen as a variant on the (compensatory) additional member system, where a set of seats are assigned by the plurality principle (but in case of the jackpot system, in a multi-member district), while the rest of the seats are assigned with the proportionality principle, taking into account the seats already distributed. This means if the majority jackpot is set at 55%, and the largest party/coalition receives 35% of the vote, they will be entitled to the additional 20% to reach 55%, but no more. The rest of the seats are distributed among the other parties, unlike the majority bonus system, which would not take them into account (like parallel voting). If the largest party would receive 60% of the vote, they would be entitled to the additional 5% of seats above the majority jackpot, unless there is also a minority jackpot. The size of a jackpot is typically above 50%, to provide for a clear majority, but may also provide for a certain size of supermajority.
  • A variant on the majority jackpot is the minority jackpot, which ensures a certain amount of minimum representation for political or minorities. A variation of the minority jackpot is lower threshold for certain minority lists or reach their first seat.
  • A jackpot system may also be conditional: it may provide for a supermajority jackpot only for a party which received an absolute majority of vote.

The majority bonus system was adopted by other European countries, especially Greece in 2004 and San Marino at the national level, and France for its regional and municipal elections.

Caciagli, Mario; Alan S. Zuckerman; Istituto Carlo Cattaneo (2001). Italian Politics: Emerging Themes and Institutional Responses. Berghahn Books. pp. 87–89.