The transition to democracy in Spain is a fine example of an electoral system that was thought to be provisional and meant to be in force only for the first democratic elections, but its core elements ended up becoming consolidated.
Decree-Law 20/77 of 18 March establishes a regulation that was in principle only intended for the first democratic elections. However, it marked the Spanish electoral system in a decisive manner, due to a combination of the following factors:
- In the first place, because many of its elements were constitutionalised. In the Spanish Constitution of 1978, which had been elaborated by the Spanish Parliament that emerged from these first elections, the number of deputies (between 300 and 400), the provincial electoral constituency and the choice of proportional representation criteria are stipulated in the regulations for Congress; and for the Senate, the election of four senators per province.
- In the second place, because its temporary application was extended. First for the 1979 elections, by transitional disposition 8, point 3, of the Constitution; then for the 1982 elections, due to the incapacity of the government of the UCD to achieve sufficient parliamentary consensus to approve an organic electoral law.
- Finally because the electoral system that had been established functioned in accordance with the objectives pursued: an acceptable degree of representativeness without excessive fragmentation of the Houses; stable governments, even with an absolute majority; the alternation of power and, as an overall consequence, a high degree of legitimacy.
Consequently, Organic Law 5/1985, of 19 June took up many elements of the 1977 decree - sometimes literally: the total number of deputies, the initial minimum for each constituency, the D¥Hont method as a concrete proportional formula, the closed, blocked lists for Congress and the essential elements for the election of senators.
The reforms subsequent to the LOREG (by organic laws 8/91; 6/92; 13/94; 3/95) did not modify the electoral system. And the electoral laws of the seventeen Autonomous Regions have also taken up the whole of the elements of the electoral system, apart from some specific points as far as constituencies are concerned. The only partial exception has been the choice of a national constituency in the elections for the European Parliament (included into the LOREG by Organic Law 1/87).
