User:WhereIsGreen/Zipper system

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The zipper system (also known as a "vertical parity" quota or the "Zebra" system ) is a type of gender quota placement mandate for party lists in proportional representation electoral systems. It requires that parties alternate between women and men on their candidate lists, meaning that 50% of the candidates are women and 50% are men. The zipper method is applied to election laws in many countries in order to achieve equal gender representation in candidates and, potentially, elected members. This system has been used in multiple different countries in the 20th and 21st centuries, and is still used in many today.

Process
The zipper system is rank-order electoral rule that requires a party to create a candidate list in which the gender of the candidates alternates between women and men. Thus, when the party is allocated seats in the legislative body, the gender of the elected members alternates for each additional seat that party won. This results in a near-fifty-fifty split between the number of women and men elected for that party. Vertical parity can also be combined with horizontal parity, which works in tandem towards the same goal.

Advantages and Drawbacks
While party-list gender quotas that require a certain percentage of candidates on a party list to be women can be effective, the quotas do not guarantee that certain percentage of the legislature to be women after the election. This is because, in the absence of a zipped list rule, women may not be present in winnable positions of the party list (i.e. women are disproportionally placed at the bottom rather than towards the top of the party list ) and are thus not elected, despite a gender quota requirement. Some research has shown that, in fact, having a gender quota with no rank order rule may be purely symbolic. Vertical parity can circumvent this problem by requiring that every other candidate be a woman, which ensures that women are placed in these winnable positions. Research has shown that the addition of the zipper system to a gender quota ensures near-parity of women and men in a legislative body for this very reason.

However, even though the zipper system rank-order rule requires a fifty-fifty split between women and men on the party list, this does not always translate to a fifty-fifty split in the legislature. Parties, while required to alternate between men and women, often put a man in the first position on the list. Thus, if parties win odd numbers of seats in a given election and if the party list begins with a man, the number of men elected will be equal to the number of women elected plus one. This gender imbalance is unavoidable in odd numbers of seats, but if the candidate at the top is consistently of one gender, this will advantage that gender (in this case, men). Since this is a common occurrence across many different constituencies and electoral districts, the gender breakdown of the final electoral body can often still be skewed towards men by small to rather significant margins. Additionally, a few studies have also shown that the assumption that women are placed at the bottom of party lists consistently is not entirely correct, making placement mandates like the zipper system a mute point. This, however, is in contrast to many other studies finding the opposite.

Horizontal Parity
''Vertical parity is sometimes combined with horizontal parity to further reduce the gender gap among elected officials. Horizontal parity is another type of zipper method in proportional party-list political systems. This system requires that each party also field an equal number of candidate lists with female candidates at the top of the list as candidate lists with male candidates at the top of the list across each constituency that the party participates. ''

Current Use
Some countries mandate the zipper system in their electoral laws. Bolivia, Costa Rica, Ecuador, France, Kenya, Lesotho, Libya, Nicaragua, Senegal, South Korea, Tunisia, and Zimbabwe all implement the zipper system through election law in at least one elected body. Of these countries, many do not use the zipper system evenly across legislative bodies, or have additional requirements. In France, only the electoral bodies that use proportional allocation of seats use the zipper system, which includes the ((FIND NAMES)). Similarly, in Zimbabwe, the zipper system is only used in the Senate elections, and only requires that 60 out of the 80 seats in the Senate apply the zipper system. In addition to vertical parity, Costa Rica uses horizontal parity system, forcing parties to alternate between women and men at the top of their lists in different provinces. Finally, while Mauritania does not use a country-wide vertical parity gender quota rule, they do require that constituencies that require three or more names on the party list to use the zipper system.

'Maybe better table here? Include country, legislative body, proportion women, horizontal parity?' In countries without a legal requirement, some parties choose to implement the zipper system on their own lists. The Swedish Social Democratic Party (SAP) introduced of the zipper system in 1993, and this led to 48% of its candidates in the 1994 general elections being women as well as a record number of female MPs being elected to the Riksdag. Until 2007, local left-wing parties in some provinces of Spain, including Andalusia, Castile-La Mancha, and the Balearic Islands, voluntarily implemented zipped candidate lists in opposition to obstruction from the Popular Party (PP) in implementing a zipped system in local election laws for these regions. With the passage of the Equality Law under the Spanish Socialist Worker's Party (PSOE), these local zipper laws were able to take effect in 2007.

Zipper systems were introduced in Italy in 1993, but overturned by the constitutional court in 1995.

v This table is from the original article and will be removed, but will change the format, use the sources, and expand on the information.