What drew you to this field?
Reia: I have always been interested in cities and how they are governed. In 2019, while working at McGill University in Montreal, I became a member of the city’s first Night Council, led by the nonprofit MTL 24/24. I worked closely with local authorities and civil society organizations to prepare reports and co-create a nightlife policy, contributing particularly to discussions on open data and artificial intelligence in relation to the urban night. Around the same time, I joined various groups of scholars and practitioners worldwide reflecting on night studies, and through one of these networks, I began collaborating with my co-investigators in Mexico and Canada.
You have commented on the need to investigate our definitions of “meaningful” or “valid” data. How would you redefine (or eliminate) those terms?
Reia: The status of data concerning the nighttime of cities has been shaped by two real or perceived features of the urban night. One is the longstanding treatment of the night as a period defined principally through its associations with criminality, danger and moral transgression. This has meant that many of the key sources of data on the nighttime activity of cities are to be found in police records, public investigations of morality, journalistic reporting on crime and other sources which emphasize the night’s supposed tendency to stimulate criminality.
Another factor limiting data availability has been the ephemerality of nighttime activity, particularly in the cultural realm. The culture of the night is very often a culture of punctuated events rather than of enduring institutions. With that in mind, I have been studying the night as a complex ecosystem that involves people, spaces, nonhumans and activities. It covers everything from snow removal and maintenance to healthcare and cultural institutions.
To truly understand the night, we need to recognize its uniqueness by looking beyond common definitions and formats, including ephemeral media, archives, citizen-generated data, and more. We want to expand what is seen, considered and used as data in nighttime policymaking.

