Ley de Lemas

Ley de Lemas is the Spanish name of the double simultaneous voting (DSV) electoral system which is, or has been, used in elections in Argentina, Uruguay, and Honduras. It employs an unusual open party-list proportional representation system, and works as follows:

The Lemas system was designed in 1870 by the Belgian professor Charles Borelli.

Lemas were introduced in Uruguay in the early 20th century when the "Lema law" introduced double simultaneous voting. It allowed for the election of the President, Chamber of Deputies and Senate by casting a single vote. Parties acted as lemas, while party factions formed sublemas. Voters would vote for a sublema of a party, with the totals of sublemas totalled to establish the winning party.

During periods in which a presidential system was enacted (as opposed to the collegiado system that operated between 1918 and 1933 and 1951 and 1966), the presidential candidate of the sublema in the winning party with the most votes would become President.

This system was abolished for presidential elections after constitutional reforms were passed in a 1996 referendum, restricting each party to a single presidential candidate.Department elections still use the old system.

The parliamentary and department elections still use double simultaneous voting.

Honduras applied the Ley de Lemas in the 1985 presidential election, when, due to factionalism within the two dominant parties, both were unable to elect a single presidential candidate.

In Argentina, a number of provinces employ or have employed a version of this electoral system: Chubut, Formosa, Jujuy, La Rioja, Misiones, Río Negro, Salta, San Luis, Santa Cruz, Santa Fe, Santiago del Estero, and Tucumán. Provinces have complete freedom to elect local and national representatives using the method of their choice; the system propagates down to the municipal level (except in the hypothetical case of autonomous cities).

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