Forcing Spanish political parties to nominate more women is helping them win votes

Susana Diaz, a candidate and voter in Andalusia, is one of a wave of new women politicians.
Susana Diaz, a candidate and voter in Andalusia, is one of a wave of new women politicians.
Image: Reuters/Marcelo del Pozo
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In 2007, Spain passed a law that took its political system by surprise. It forced parties contesting local elections to make sure 40% of their candidates were women–an unprecedented proportion for a country that has never had a female presidential candidate and that still favors princes over their older sisters when it comes to passing on the throne.

Eight years on, it turns out the policy has had an effect beyond making political parties more equal. It has also made them more popular.

Researchers at the Massachusetts Institute of Technology and Arizona State University studied voting patterns (pdf) in Spanish towns with populations over 5,000, where the Equality Law applied, and compared them to towns with smaller populations that were exempt from the rules.

The law led to an increase of 35% in the number of women candidates—some parties had to make bigger changes than others, because they had started off with fewer women on their tickets. And parties that were forced to make larger relative increases did better than other parties in the same municipalities.

What happened was this. All parties had to increase the proportion of women candidates until they reached the 40% threshold. But those parties that had to increase the number of female candidates more greatly–because they started with fewer–saw gains relative to their rivals. Parties forced to increase the proportion of female candidates by 10 percentage points more than their opponents saw a gain in votes. On average, 20 out of 1,000 voters switched to those parties–giving the parties that had made the biggest changes a 4.2-percentage-point gain over their rivals.

“The effect is non-negligible, and it’s positive,” Albert Saiz of MIT, one of the researchers, told MIT News.

The effect of gender equality quota policies is often complex and hard to measure. In the corporate sector, where quotas for women on boards and at other levels of management are being discussed in many countries and enacted in some, outcomes–positive or negative–are mostly yet to proven. But the nature of politics, in which public votes are key, gave the Spain researchers a way to quantify how much the quotas affected attitudes.

They also noted that many potential problems with having more women on political tickets failed to materialize. People in the affected towns did not vote less. And the parties did not particularly have trouble finding suitable female candidates.

Several justifications for the small number of female political candidates found in many countries are therefore undermined—including the ideas than women are less popular with the electorate, and that there are not enough women eager to fill the roles on offer.

The researchers suggest another reason for the inequality: internal party dynamics.

It’s not really about the voters, Saiz told MIT News: “There’s some elbowing out going on that leaves women behind.”