Binomial voting system
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The Binomial System is a voting system used in the parliamentary elections of Chile. Its use was prescribed in the respective constitutional organic law during the Pinochet regime. The Binomial System was invented in Poland Wojciech Jaruzelski's period and implemented by the Pinochet regime to foster political stability. Its recognized like a system that promoted consensus and negotiation between opposing sides of government.
Characteristics
The system works in the following manner: Parties and independent candidates group themselves into lists or coalitions, basically electoral blocs. Each list proposes up to two candidates per electoral region, province, or other geographical unit. Votes are first tallied by list instead of by candidate, and unless the list which obtained the first majority has double the voting as the second majority, each of the two lists gets one of their candidates, the one who got the most voting, into office. In other words, the binomial system basically means that the first and the second majority get equal representation unless the first majority doubles the second. For example, in the following cases the candidate that would get elected under a binomial system are marked with an [e]:
| Case 1 | Case 2 | Case 3 | Case 4 | |
|---|---|---|---|---|
| List 1 | 40% | 50% | 60% | 39% |
| Candidate 1A | 30% [e] | 30% [e] | 50% [e] | 20% [e] |
| Candidate 1B | 10% | 20% | 10% [e] | 19% |
| List 2 | 40% | 30% | 30% | 33% |
| Candidate 2A | 22% [e] | 18% [e] | 18% | 18% [e] |
| Candidate 2B | 18% | 12% | 12% | 15% |
| list 3 | 20% | 20% | 10% | 28% |
| Candidate 3A | 11% | 11% | 6% | 26% |
| Candidate 3B | 9% | 9% | 4% | 2% |
The most common case is Case 2, in which one list gets a total voting that is higher than the other but both get exactly the same amount of candidates elected, candidates 1A and 2A respectively. In the unlikely case that both lists get exactly the same amount of votes each gets a candidate into office. Only in the case that List 1 doubles the voting of List 2 will List 1 be able to get two seats, even if, like in Case 3, the second elected candidate of the majority list received less voting of all the candidates of the two majorities. Also, it makes it very difficult for minority parties to elect candidates; in Case 4 candidate 3A receives the most votes, and however, under the binomial system, it will be candidates 1A and 2A that will be elected.
As can be seen, the binomial system acts to equalize the representation of the second majority to the point of making it roughly equal, or only slightly smaller, than that of the first majority. Furthermore, it acts to exclude any minority from the process, in practice generating a locked two-party, or two-bloc, system in which it's exceedingly difficult for one of the blocs to get an upper hand on the other. The table below posits the electoral results of the 2005 lower chamber parliamentary elections with three different voting systems.
| Concertación Democrática, a centre-left coalition |
Alianza, right wing conservatives | Juntos Podemos Más, left wing progressives, ecologists, and others | Fuerza Regional Independiente, obsolete regionalist movement | |||||
|---|---|---|---|---|---|---|---|---|
| Binomial | 65 dip. | 54,2% | 54 dip. | 45,0% | 0 dip. | 0,0% | 1 dip. | 0,83% |
| Direct Election | 69 dip. | 57,5% | 50 dip. | 41,6% | 0 dip. | 0,0% | 1 dip. | 0,83% |
| Proportional System | 62 dip. | 51,6% | 46 dip. | 38,3% | 9 dip. | 7,5% | 1 dip. | 0,83% |
Rationale
The binomial system, proponents argue, acts to stabilize the political[1] situation by making it almost impossible for a single political bloc or coalition to make important choices in a one-sided manner. This in turn leads to great political stability and prevents the emergence of the long-term personality-centred populist regimes that have been common throughout the history of Latin America. It has also been argued that it fosters consensus-building, debate and negotiation. Finally the point of representation is often cited in defence of the binomial system, as it provides a representation to the big minority that first-past-the-post systems don't.
Criticism
Critics of this system argue that it makes for a flawed democracy, as it doesn't necessarily elect the candidate which received the most votes, this is, it fails the majority criterion, amongst other things. Another of its perceived disadvantages is that it, in the Case of the Chilean situation, consistently benefits one of the two political blocs, the Alianza, which consistently gets around 40% of votes and receives nearly 50% of the seats, this is, it consistently over represents one of the political sectors. Furthermore, it excludes the smaller political blocs like the Juntos Podemos Más. Finally, it is considered greatly responsible in the fact that the Chilean Constitution, originally written and enforced by an authoritarian military dictatorship, hasn't been changed significantly.
References
- Von Baer, Ena: "Sistema Binomial: Consensos y disensos, en Reforma al Sistema Binomial chileno (Santiago, PNUD, 2006) pp. 177-206.
- Carey, John M.: "Las virtudes del sistema binomial", en Revista de Ciencia Política, Vol.26 N°1 (2006), pp. 226–235.
- Chilean law regulating the voting process [1]