From the beginning, the reforms were controversial. Thousands of court workers went on strike to protest the constitutional amendment. Some protesters even stormed the Senate building.
Critics accused the Morena party of seeking to strengthen its grip on power by electing sympathetic judges. Already, the party holds majorities in both chambers of Congress, as well as the presidency.
Opponents also feared the elections would lead to unqualified candidates taking office.
Under the new regulations, candidates must have a law degree, experience in legal affairs, no criminal record and letters of recommendation.
Candidates also had to pass evaluation committees, comprised of representatives from the executive, legislative and judicial branches of government.
And yet, some of the final candidates have nevertheless raised eyebrows. One was arrested for trafficking methamphetamine. Another is implicated in a murder investigation. Still more have been accused of sexual misconduct.
Arias suspects that some candidates slipped through the screening process due to the limited resources available to organise the election.
She noted that the National Election Institute had less than 10 months to arrange the elections, since the reforms were only passed in September.
“The timing is very rushed,” she said.
One of the most controversial hopefuls in Sunday’s election is Silvia Delgado, a lawyer who once defended the cofounder of the Sinaloa Cartel, Joaquín “El Chapo” Guzman.
She is now campaigning to be a judge in Ciudad Juarez, in the border state of Chihuahua.
Despite her high-profile client, Delgado told Al Jazeera that the scrutiny over her candidacy is misplaced: She maintains she was only doing her job as a lawyer.
“Having represented this or that person does not make you part of a criminal group,” she said.
Rather, she argues that it is Mexico’s incumbent judges who deserve to be under the microscope. She claimed many of them won their positions through personal connections.
“They got in through a recommendation or through a family member who got them into the judiciary,” she said.
President Sheinbaum has likewise framed the elections as part of the battle against nepotism and self-dealing in the judicial system.
“This is about fighting corruption,” Sheinbaum said in one of her morning news briefings. “This is the defence of the Mexican people for justice, for honesty, for integrity.”