Alberto Hernández.


Two months after the 2015 autonomic election, the Regional Assembly of Murcia passed a law which reformed the electoral system and eliminated the five electoral districts. In this post I will analyse the previous system with reference to its direct consequences in Murcian politics. Specifically, I will focus on the following hypothesis: The electoral system was the main factor that influenced the party system to date.

The current law (modified in 2015) was approved by the pre-autonomous Government due to an agreement between the Socialist Party (PSOE) and Union of Democratic Center (UCD), but with no consensus with other political parties such as People’s Alliance (AP, post-francoist right), Communist Party (PCE) and Cantonal Party (PCAN, Cartagenerist). So one can say that there was some electoral interest behind the agreement (Sierra, 2015). Nonetheless, when the People’s Party (PP, before AP) became the predominant party and came to power in 1995, it started to benefit from the law, ergo it was not removed. This phenomenon is named the Inertia Law (Nohlen, 1984). Aforementioned, the Electoral system in the region established five districts which presented many inequalities and gave more priority to territoriality than proportionality. The rural areas (Noroeste and Altiplano) in general are overrepresented, and the urban areas (Vega del Segura, Valle del Guadalentín and Campo de Cartagena) are underrepresented. The intention here is to link aspects of the elections and party system with Duverger’s theory, who claimed that the electoral system was the main element configuring the result of the election (1950) and it corresponds to the idea that the smaller the district, the less proportional will be in relation to the distribution of seats. Following Penadés classification (1999), two Murcian districts had a majoritarian system (1-5 seats; Noroeste and Altiplano), one intermediate (6-9 seats; Río Guadalentín) and two  proportional (more than 10; Campo de Cartagena and Vega del Segura).

There has been nine elections for the Regional Assembly. In these elections only six out of fifty-five candidatures (with the previous names already included) have obtained a seat in this parliament (AP/CP/PP, PSOE/PSRM, PCE/IURM-LV and CDS) and until 2015 the winning party had held the absolute majority of the deputies (23 out of 45), but not always in popular vote. It’s the case of PSOE in 1987 and in 1991 (with just over 40% of the vote) and the PP in 2015 (with less than 38% of the vote). To prove this with empirical data I’ll use the advantage ratio, which divides the percentage of seats by the percentage of popular vote, <1 being an under-represented party and >1 an over-represented one. As one can see in the graph, PP and PSOE have always been over-represented (or at least proportionally represented). In 2015, the highest numbers belonged to PP and in 1987 they belonged to PSOE. On the flip side of the coin, PCE/IURM-LV and CDS have always been under-represented.

As previously stated, the cause of this voting distortion seems to be within the electoral district division. Murcia and Asturias are the only uni-provincial regions divided into districts for their Autonomous Parliamentary election. Nevertheless, Murcia and Valencia are the only regions that impose a minimum percentage (5%) in the whole region and not in the electoral district. For this reason, the Cantonal Party (PCAN) in 1987 and 1991, Union, Progress and Democracy (UPD) in 2011 and United Left (IU) in 2015 didn’t reach the deputy in Campo de Cartagena (PCAN) and Vega del Segura (UPyD and IU). In consequence, the system has been accused of Gerrymandering, that is, the manipulation of the electoral boundaries to get a partisan purpose.

Javier Sierra Rodríguez (2015) concluded in his work that Vega del Segura (C3) was the most proportional district, followed by Campo de Cartagena (C2).  Valle del Guadalentín has presented less proportionality from 2007, just like Noroeste (C4) from 2011. His study showed Altiplano (C5) as less proportional due to the number of voters. In fact, the combined effect of a high concentration in vote (the sum of PP and PSOE) and a low number in voters in the areas of Noroeste and Altiplano make it nearly impossible for small parties to gain a seat, what Baras y Botella (1996) called “bipartidismo circunscripcional

In conclusion, the previous system did influence the party system. First, because the minimum percentage required in the whole region was too high to localist movements, such as the Cantonal Party, and in general for the minorities (UPyD). Second, because the electoral districts division over-represented bipartisanship at expense of the under-represented minorities (CDS, IU). And third, because rural districts present a high concentration of PP and PSOE, so there could be a discouragement in voting for the minoritarian parties because it is useless. The new law establishes just one electoral district and a minimum of 3%, so we could see more parliamentary parties in the next term, and even the resurgence of localist movements.

Source: Data from Sierra, J. (CROEM)–Own elaboration



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  • DUVERGER, M. (1950). L’influence des systèmes électoraux sur la vie politique, Armand Colin, Paris.
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