She was the creator of Ronda Maria da Penha, a programme of the Military Police of Bahia (PMBA) aimed at combatting domestic violence.

She was encouraged by her father to enter the military police after completing high school in 1990, because it would provide her with a reliable income.

Santiago later graduated in psychology and then obtained a master's degree in territorial development and social management from the Federal University of Bahia (UFBA).

She also took a number of other courses, such as on cognitive behavioural therapy at the Federal University of São Paulo (UNIFESP) and on assistance to women victims of violence, at the National Secretariat of Public Security (SENASP).

She was unsuccessful in the election for mayor, coming second, ahead of Pastor Sargento Isidório of Avante, but losing to incumbent Bruno Soares Reis of DEM.