Facial recognition and other biometric data are presented as a type of personal data that allows security forces to manage the security of urban spaces with supposed greater certainty, for example, identifying and verifying pedestrians in search of fugitives or dangerous people. There is an entire market of facial recognition systems, and other biometric data, to which states today turn in search of reinforcing the narratives of surveillance, control, and security in cities, but are they really efficient? What are we doing and giving up in exchange?