Enhancing public trust and police legitimacy during road traffic encounters: results from a randomised controlled trial in Scotland

This paper reports results from the Scottish Community Engagement Trial (ScotCET), devised to replicate the Queensland Community Trial (QCET). ScotCET was an RCT that tested the effects of 'procedurally just' policing on public trust and police legitimacy A block-randomised (matched pairs) design, with pretest and posttest measures, was implemented in the context of road policing in Scotland. Participants were drivers stopped by police in December and January 2013/14 as part of Police Scotland's 'Festive Road Safety Campaign'. The experimental intervention comprised a checklist of key messages to include in routine roadside vehicle stops, and a leaflet for officers to give to drivers. Analysis proceeds via random effects regression models predicting latent variable measures of trust, satisfaction and legitimacy Contrary to expectations, the intervention did not improve trust and legitimacy; rather, trust in the officers who made the stop, and satisfaction with their conduct, fell in the test sites, relative to the controls, after implementation of the intervention. The intervention had no significant effect on general trust in the police, nor on police legitimacy Results demonstrate the difficulty in translating experimental interventions across policing contexts, and challenge the notion that public perceptions may be improved through a simple, additive approach to the delivery and communication of procedural justice.