Some weeks ago, this blog reviewed the benefits and challenges that the ex-head of the Spokane county police force (Washington) related with the use of body cams by law enforcement agencies. The proliferation of this type of appliance has created a need to assess its use and efficiency based on experimental evidence.
Last May the magazines European Journal of Criminology and Journal of Experimental Criminology published the first results of research which analysed the use of such appliances in eight different police forces in the United Kingdom and the United States. The researchers took into account the basic reasons for introducing such appliances which are to reduce the use of force on the part of the police and reduce the number of complaints against the police. The objective of the study was therefore to decide if recording images and sounds relevant to interaction between the police and the public influenced the use of force by the police against the public or the public against the police.
To achieve this, they carried out 10 controlled random tests and experiments during which they gathered information from almost 2.2 million hours of work by 2,122 police officers belonging to eight different police forces (in the case of two of the forces they analysed two different zones). At the start of each week, shifts were randomly assigned to different police officers some carrying cameras and some not, and data was gathered related to arrests carried out, the number of cases which involved the use of force by the police and the cases in which the police had been the object of aggression.
Although the collective preliminary results of this research stress that a significant effect of the use of cameras has not been detected in relation to the use of force by the police, there are some noteworthy conclusions. On the one hand, analysing cases individually, there are places where the use of force has increased and others where it has decreased; moreover, it has been demonstrated that agents were more likely to be assaulted when they were carrying cameras rather than when they were not. It would appear the act of discretion as to when to turn on or turn off the appliance is a parameter to be kept in mind, as forces whose agents always had the appliances turned on saw a 37% reduction in the use of force compared to agents who were not carrying cameras, whereas cases in which officers turned the cameras on and off at their discretion experienced a 71% increase in the use of violence in comparison with agents who were not carrying cameras. In the future, researchers hope to be able to offer more eloquent results based on the information gathered.
The studies published are the following:
Ariel et al. “Report: increases in police use of force in the presence of body-worn cameras are driven by officer discretion: a protocol-based subgroup analysis of ten randomized experiments”. Journal of Experimental Criminology. 2016. 1-11. DOI: 10.1007/s11292-016-9261-3
Ariel et al. “Wearing body cameras increases assaults against officers and does not reduce police use of force: Results from a global multi-site experiment”. European Journal of Criminology. 2016. 1-12. DOI: 10.1177/1477370816643764
The RAND Corporation published a site abstract investigation.