Additional information about gender quotas

Mexico
In February 2014, Mexico passed a constitutional amendment to the Article 41 of the Federal Constitution requiring that that political parties develop "...rules to ensure gender parity in the nomination of candidates in federal and local congressional elections." This amendment marks a critical improvement over the past constitutional requirement of 40-60 % representation of either sex in the Assembly, and requires parity and alternation between women and men on parties’ candidate lists. According to the OAS Preliminary Report on the 2018 Mexican elections, the constitutional amendment gave way for legal reforms and that "Mexico has developed a robust body of legislation to ensure gender parity and equality, which has been accompanied by effective action by the electoral bodies." The results from the 2018 elections saw a significant increase of women in both parliament and senate. Although the legal provisions have been effective in increasing women's political participation, they do not apply to the single-member posts, women are still in clear minority (as in the presidential election) which shows the remaining barriers for women to participate on equal grounds.
“Mexico is only the third country in Latin America to enact a gender parity law for its national legislature and is proud to have the highest percentage of women in the Senate and fourth-highest in the House of Representatives of any Latin American country. While the previous round of reforms had increased the minimum quota of women from 30 percent of the list to 40 percent, parties were avoiding the quota by holding primary elections, a loophole that is now closed.”
“Within the framework of the previous federal electoral process (2012), and because of the parties’ lack of compliance with the gender quota when nominating candidates—due to the application of a selection process based on the democratic processes foreseen by their statutes—the Electoral Court of the Judicial Power of the Federation passed a sentence that solved the supremacy of the gender quota over any other internal selection procedure to nominate candidates used by the political parties, including the internal elections.” The Assembly set 30 April 2014 as the deadline for developing a set of amendments to the electoral legislation to set out detailed rules for implementing this constitutional amendment through laws regulating electoral processes and the operation of political parties.
On June 6, 2021, Mexico implemented its constitutional mandate for “gender parity in everything” for the first time. In 2018, women won half the seats in Mexico’s Congress. Mexico championed a groundbreaking constitutional reform: gender parity for all candidates for elected office, and for top posts in the executive and judicial branches. Called “parity in everything,” the reform sailed to victory in May 2019. Not a single member of Congress voted against it (MSMagazine, 2021).