In the past decade, 21 countries have adopted gender quota laws that require between 20% and 50% of all legislative candidates to be women. What explains the adoption of these laws? I argue that three factors make politicians more likely to adopt gender quota laws. First, electoral uncertainty creates an opportunity for internal party reform that factions within a party can exploit to their advantage. Second, the courts play an important role because of the centrality of the issue of equal protection under the law to gender quotas. Finally, cross‐partisan mobilization among female legislators raises the costs of opposing such legislation by drawing public attention to it. I examine these three claims with regard to Mexico, where the federal congress passed a 30% gender quota law in 2002.

I'd give up my seat for you if it wasn't for the fact that I'm sitting in it myself.

—Groucho Marx

(quoted in Abdela 2001)

[Many Latin American countries] have ‘homosexual’ political systems, that is, the power of the political parties and the state is in the hands of only one of the sexes.…

—Line Bareiro, Paraguayan feminist

(Bareiro and Soto 1992, 11)