Reimagining the familiar stranger as a source of security: generating guardianship through everyday mobility

The familiar stranger is a social phenomenon that emerges from the serial reproduction of daily routines, structured around urban places and practices, that results in repeated encounters with the same individuals over time. Scholarship suggests that increased familiarity among individuals might incur crime control benefits at places by reducing individual anonymity and enhancing the moral obligation to obey behavioural norms. Familiarity with place-based norms and regularities can also enhance guardianship capacity and willingness to intervene when problems arise. In this paper, we detail a framework that integrates geographical, sociological, and psychological understandings of urban daily life to conceptualize the familiar stranger as a uniquely urban phenomenon emerging from multiple social processes synchronising in time-space. Our framework highlights the capacity for variation in relation to intensity contingent on daily regularities, place attributes, structures and social norms and provides for future measurement, modelling, and monitoring of familiar strangers as a protective factor against crime that can be ascribed to individuals, places and/or social systems. We include an operationalisation of our framework for a single use case, namely familiar stranger encounters in a public transit network.