Won the municipal election in her hometown on Nov 4, 2007, but her victory was annulled because she was a woman.
On November 4, 2007, Eufrosina Cruz won the municipal election to become President (mayor) of her hometown, Santa María Quiegolani, Oaxaca. Despite receiving sufficient community support at the ballot box, local authorities operating under the usos y costumbres (customary law) system annulled her victory, citing tradition that barred women from holding public office in the municipality.
The annulment sparked outrage and drew significant national and international attention to the plight of indigenous women in Mexico, who in many communities governed by customary law were denied not only the right to hold office but often the right to vote at all. Cruz's case became emblematic of the tension between indigenous self-governance traditions and constitutionally guaranteed individual rights, particularly gender equality.
Rather than retreating, Cruz used the injustice as a catalyst, publicly denouncing the discrimination and beginning a national campaign for the political rights of indigenous women. This moment marked the true beginning of her activist and political career, and it laid the groundwork for the legal and constitutional reforms she would go on to champion in the following years, both at the state and federal levels in Mexico.