Police legitimacy is a core concept in policing as it is closely connected to the fundamental element of “policing by consent”, affecting the rightfulness of the state police’s exercise of power and citizens’ decisions as to whether or not to obey police instructions. Developments in technology have significant impacts on policing and the broader ‘visibility’ of policing. Increased scrutiny of policing practices has the potential to expose, and bring to the fore, negative images of individual police officers, which is likely to lead to scandals and even reputational crises for the police organisation. Thus, the new visibility of policing on social media can significantly affect police legitimacy. This research examines police communication at the local force level via social media, namely Twitter, to engage with citizens. It questions if, and how, the police enhance and repair legitimacy via Twitter, comparing the different operational tactics of deployment of social media.

Employing a mixed-methods research design, this study explores the current police communication via Twitter in two police forces located in England and Wales. Fieldwork has been conducted in the offices of the two force corporate communication branches (as called corporate communication department in Hawshire), in particular, seven semi-structured interviews and two focus groups with nine Communication Officers from Hawshire and five interviews and one focus group with three officers from Lionshire Police force, one communication training session in Hawshire, and a two-night’ shift patrol with an undercover team of Lionshire Police. Building upon the analysis of interviews, focus groups, and field notes, documentary analysis of the official communication guidance and training materials from the two forces, ACPO, NPCC, and the College of Policing was employed, and a total of 840 and 1521 posts were collected respectively from police corporate Twitter accounts for analysing themes and patterns of the police tweets. In so doing, this thesis provides a comprehensive assessment of how Communication Officers operate police Twitter, how different individual police forces use social media, and a wealth of data to suggest how the police conduct image work via social media.

This research proposes that police forces attempt to enhance police legitimacy via social media, both for external and internal audiences. In order to achieve a positive and active engagement, individual police forces employ different communication strategies to encourage public engagement, producing various themes within the posts. Internally, the Corporate Communication department people were making efforts to communicate with police officers to enhance a sense of occupational satisfaction and self-legitimacy by posting positive stories of the police and signal markers of policing work. Externally, the police used Twitter to present an image of holding shared values with their different publics, especially seeking to provide evidence of effective policing and trustworthiness. In so doing, the posts served to also ‘teach’ police officers to be self-legitimate, and jointly produce and enhance police legitimacy.

In addition, while there are many advantages of the police use of social media, this study suggested that the ‘new visibility’ (Goldsmith, 2010) of the police on social media is, paradoxically, one of the obstacles hindering Communication Officers’ willingness to use social media. The heightened visibility has the potential to threaten individual officers’ careers, as well as the organization’s reputation. In order to minimize such risks, Communication Officers were required to conduct communication under strict rules and constraints - both on and off duty - therefore striking a balance between promoting the police image and managing the risk communication. At last, it is noted that while there are differences between the posted themes in the two research sites, both police forces acknowledged the importance of appearing personable (‘being human’) when conducting communication via Twitter – in other words presenting police as approachable and likeable characters. However, rather than emphasizing an engaging character on all police corporate Twitter accounts, this thesis argued that different police Twitter accounts with varied focuses and functions are likely to be more conducive in communication and enhancing police legitimacy.