Skip to main content
Log in

Measuring the Direct and Spillover Effects of Body Worn Cameras on the Civility of Police–Citizen Encounters and Police Work Activities

  • Original Paper
  • Published:
Journal of Quantitative Criminology Aims and scope Submit manuscript

Abstract

Objectives

Existing research on the effects of body-worn cameras (BWCs) have found largely consistent results regarding direct significant reductions in citizen complaints and often also report reductions in use of force reports. However, few studies have examined possible spillover effects onto untreated officers. This study explicitly tests for direct and spillover effects of BWCs on the civility of police-citizen encounters and police work activities.

Methods

This study assesses the direct effects of BWCs on citizen complaints, police use of force, and police proactivity and discretion during a 1-year randomized controlled trial in the Boston Police Department. Through a simultaneous quasi-experimental design, this study also investigates whether BWC deployment results in spillover effects onto control officers in treated districts as compared to comparison officers in untreated districts.

Results

Findings indicate that the use of BWCs reduces citizen complaints and police use of force but has no appreciable impact on officer activity or discretion. Furthermore, results indicate significant spillover reductions in citizen complaints for control officers in treated districts.

Conclusions

The results of this study suggest that a limited BWC adoption may generate spillover deterrent impacts as officers and citizens perceive an increased threat that inappropriate and illegal behaviors will be captured on video even when BWCs are not actually present during an encounter. Partial BWC implementation seems like a cost-effective alternative to full implementation. However, police executives and policy makers need to think carefully about possible negative externalities generated by uneven BWC coverage.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1

Similar content being viewed by others

Notes

  1. General-purpose law enforcement agencies include municipal, county, and regional police departments; sheriffs’ offices with law enforcement duties; and primary state and highway patrol agencies (Hyland 2018).

  2. It is worth noting here that it remains unclear whether observed reductions in citizen complaints reflect actual changes in the civility of police-citizen encounters. Complaint reductions may also reflect changes in citizen reporting behaviors driven by a decreased propensity to file frivolous complaints against officers (see Lum et al. 2019 for a discussion).

  3. https://www.bwcscorecard.org/static/policies/2016-07-12%20Boston%20-%20BWC%20Policy.pdf (Accessed November 21, 2018).

  4. Since there was an odd number of policing districts, one district would necessarily be excluded from the matched pairs. BPD District C-6 (South Boston) was not included in the matching process because it was not a good match for the other districts. This was primarily due to the unique presence of a majority white population with higher levels of concentrated disadvantage. It is also important to note here that District A-15 (Charlestown) is a subcommand of District A-1 (Downtown) and not a stand-alone BPD policing district. As such, District A-15 was not included in the matching exercise as there is no other similar subcommand in Boston.

  5. The non-random selection of the YVSF stemmed from two complementary interests. First, the BPD wanted to develop policy and programmatic information on the issues involved in assigning cameras to plainclothes officers relative to uniformed officers. Second, during conversations with community groups on the BWC implementation, community leaders generally recognized YVSF as a key BPD unit engaged in proactive policing activities centered on youth living in disadvantaged minority neighborhoods. These leaders requested that YVSF officers also wear BWCs during the pilot program.

  6. It is possible that BWC officers served as back-up to control officers and did not report their presence to the BPD dispatcher. Given limited funds, we were not able to conduct a field test of this hidden source of contamination that was not captured in the call data. As such, our analyses might be biased to an unknown degree by any BWC officers who did not notify their presence to the dispatcher when backing up control officers during the intervention period.

  7. An index measuring concentrated social disadvantage was calculated by standardizing and summing the following block-group level variables from the 2015 ACS: the percentage of families below the poverty level; percentage of households receiving public assistance; percentage of female-headed households with children; and percentage of the population unemployed.

  8. The 5 control districts were A-1 (Downtown), A-7 (East Boston), C-11 (Dorchester), E-13 (Jamaica Plain), and E-5 (West Roxbury). The 5 treatment districts were B-2 (Roxbury), B-3 (Mattapan), D-4 (Back Bay/South End), D-14 (Allston/Brighton), and E-18 (Hyde Park).

  9. Districts B-2 and B-3 have majority black residential populations (45.3% and 79.5%, respectively). Fagan et al. (2016) found a strong association between the percentage of black residents and the number of FIO encounters reported by the BPD in Boston neighborhoods, controlling for crime and other factors. Two sample t tests of means and two sample z tests of proportions were performed on the matching covariates reported in Table 3. None of the differences reported between the treatment and control districts were statistically significant at the p < .05 level (e.g., percent black residents = -20.8% difference, z = .74, p = .459). Given the small numbers of districts in the two samples (n1 = 5, n2 = 5), the two sample tests were not adequately powered to detect bona fide differences. As such, the results of these hypothesis tests were not robust enough to be reported here.

  10. ACU plainclothes officers assigned to the control districts were included as counterfactuals for the YVSF officers in the control group. ACU officers work to apprehend repeat offenders and increase police presence in crime hot spots within districts. While the foci of ACU activities are broader, the ACU and YVSF engage in similar proactive policing tactics. The matching exercise included n = 38 eligible ACU officers.

  11. Post-estimation likelihood ratio tests confirmed that these outcomes were distributed as Poisson rather than negative binomial processes. For the citizen complaints model, the likelihood χ2 (df = 1) = .78, p = .188. For the officer use of force reports model, the likelihood χ2 (df = 1) = 1.75, p = .093.

  12. These intervention period differences are slightly larger than what was reported in an unpublished preliminary impact evaluation report (see Braga et al. 2018a). The discrepancy is due to a reporting lag in the entry of complaints and use of force reports into the data systems maintained by the BPD Bureau of Professional Standards when the preliminary data were provided to the research team in September 2017. There are no time constraints limiting when complainants can file Internal Affairs Division complaints against BPD officers. Officer use of force reports are investigated and reviewed by an established chain of command.

  13. Note that the program impacts were robust across a variety of matching algorithms and caliper/bandwidth selections: radius matching (caliper .1, .01); Gaussian kernel matching (bandwidth = .01, .001), Epanechnikov kernel matching (bandwidth = .1, .01), and simple nearest neighbor matching. Although the estimates differed slightly across the varying propensity score matching methods, the BWC treatment statistically-significant spillover effect on officer complaints remained robust while the spillover effect on officer use of force reports never reached the less restrictive p < .10 level of significance.

References

  • Apel R, Sweeten G (2010) Propensity score matching in criminology and criminal justice. In: Piquero A, Weisburd D (eds) Handbook of quantitative criminology. Springer, New York, pp 543–562

    Google Scholar 

  • Ariel B, Farrar T, Sutherland A (2015) The effect of police body-worn cameras on use of force and citizens’ complaints against the police: a randomized controlled trial. J Quant Criminol 31:509–535

    Google Scholar 

  • Ariel B, Sutherland A, Henstock D, Young J, Drover P, Sykes J, Megicks S, Henderson R (2016a) 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. J Exp Criminol 12:453–463

    Google Scholar 

  • Ariel B, Sutherland A, Henstock D, Young J, Drover P, Sykes J, Megicks S, Henderson R (2016b) Wearing body cameras increases assaults against officers and does not reduce police use of force: results from a global multi-site experiment. Euro J Criminol 13:744–755

    Google Scholar 

  • Ariel B, Sutherland A, Henstock D, Young J, Drover P, Sykes J, Megicks S, Henderson R (2017) “Contagious accountability”: a global multisite randomized trail on the effect of police body-worn cameras on citizens’ complaints against the police. Crim Just Behav 44:293–316

    Google Scholar 

  • Ariel B, Sutherland A, Henstock D, Young J, Drover P, Sykes J, Megicks S, Henderson R (2018a) Paradoxical effects of self-awareness of being observed: testing the effect of police body-worn cameras on assaults and aggression against officers. J Exp Criminol 14:19–47

    Google Scholar 

  • Ariel B, Sutherland A, Sherman L (2018b) Preventing treatment spillover contamination in criminological field experiments: the case of body-worn police cameras. J Exp Criminol. https://doi.org/10.1007/s11292-018-9344-4

    Article  Google Scholar 

  • Austin P, Grootendorst P, Anderson G (2007) A comparison of the ability of different propensity score models to balance measured variables between treated and untreated subjects: a Monte Carlo study. Stat Med 26:734–753

    Google Scholar 

  • Blalock HM (1979) Social statistics, 2nd edn. McGraw-Hill, New York

    Google Scholar 

  • Braga A, Barao L, McDevitt J, Zimmerman G (2018a) The impact of body-worn cameras on complaints against officers and officer use of force incident reports: Preliminary evaluation findings. Northeastern University, Boston

    Google Scholar 

  • Braga A, Sousa W, Coldren J, Rodriguez D (2018b) The effects of body-worn cameras on police activity and police-citizen encounters: a randomized controlled trial. J Crim Law Criminol 108:511–538

    Google Scholar 

  • Brown GR (2016) The blue line on thin ice: police use of force modifications in the era of cameraphones and YouTube. Brit J Criminol 56:293–312

    Google Scholar 

  • Caliendo M, Kopeinig S (2005) Some practical guidance for the implementation of propensity score matching. Institute for the Study of Labor, Bonn

    Google Scholar 

  • Campbell D, Stanley J (1963) Experimental and quasi-experimental designs for research. Rand McNally, Chicago

    Google Scholar 

  • Card D, Krueger A (1994) Minimum wages and employment: a case study of the fast-food industry in New Jersey and Pennsylvania. Am Econ Rev 84:772–793

    Google Scholar 

  • City of Boston Mayor’s Office (2018). Mayor announces next steps towards implementation of body cameras. Retrieved from https://www.boston.gov/news/mayor-announces-next-steps-towards-implementation-body-cameras. Accessed 2 Jan 2019)

  • Clarke RV (1989) Theoretical background to crime prevention through environmental design (CPTED) and situational prevention. In: Geason S, Wilson P (eds) Designing out crime: the conference papers. Australian Institute of Criminology, Canberra, Australia, pp 1–8

    Google Scholar 

  • Clarke RV, Weisburd D (1994) Diffusion of crime control benefits: observations on the reverse of displacement. Crime Prev Stud 2:165–184

    Google Scholar 

  • Cohen J (1988) Statistical power analysis for the behavioral sciences. Lawrence Earlbaum Associates, Hillsdale

    Google Scholar 

  • Consulting ODS (2011) Body worn video projects in paisley and aberdeen. Self Evaluation, ODS Consulting, Glasgow

    Google Scholar 

  • Cook T, Campbell D (1979) Quasi-experimentation: design and analysis issues for field settings. Rand McNally, Chicago

    Google Scholar 

  • Crow M, Snyder J, Crichlow V, Smykla JO (2017) Community perceptions of police body-worn cameras: the impact of views on fairness, fear, performance, and privacy. Crim Just Behavior 44:589–610

    Google Scholar 

  • Dehejia R, Wahba S (2002) Propensity score matching methods for nonexperimental causal studies. Rev Econ Stat 84:151–161

    Google Scholar 

  • Demir, M., Apel, R., Braga, A., Brunson, R., and Ariel, B. (2018). Body worn cameras, procedural justice, and police legitimacy: a controlled experimental evalution of traffic stops. Just Q, pp 1–32

  • Doyle A (2011) Revisiting the synopticon: reconsidering Mathiesen’s ‘The Viewer Society’ in the age of Web 2.0. Theor Criminol 15:283–299

    Google Scholar 

  • Duval TS, Wicklund R (1972) A theory of objective self-awareness. Academic Press, New York

    Google Scholar 

  • Evans R (2015) ‘The footage is decisive’: applying the thinking of Marshall McLuhan to CCTV and police misconduct. Surv Soc 13:218–232

    Google Scholar 

  • Farrar T, Ariel B (2013) Self-awareness to being watched and socially desirable behavior: a field experiment on the effect of body-worn cameras and police use of force. Police Foundation, Washington

    Google Scholar 

  • Fagan J, Braga A, Brunson R, Pattavina A (2016) Street stops, race, and surveillence in the new policing. Fordham Urb Law J 42:621–696

    Google Scholar 

  • Foucault M (1977) Discipline and punish: the birth of the prison. Vintage, New York

    Google Scholar 

  • Ganascia JG (2010) The generalized sousveillance society. Soc Sci Inform 49:489–507

    Google Scholar 

  • Goldsmith AJ (2010) Policing’s new visibility. Brit J Criminol 50:914–934

    Google Scholar 

  • Goodall M (2007) Guidance for the police use of body-worn video devices. Home Office, London

    Google Scholar 

  • Grossmith L, Owens C, Finn W, Mann D, Davies T, Baika L (2015) Police, camera, evidence: london’s cluster randomised controlled trial of body worn video, College of Policing Limited and the Mayor’s Office for Policing and Crime, London

  • Guerette R, Bowers K (2009) Assessing the extent of crime displacement and diffusion of benefits: a review of situational crime prevention evaluations. Criminology 47:1331–1368

    Google Scholar 

  • Haggerty KD, Wilson D, Smith GJD (2011) Theorizing surveillance in crime control. Theor Criminol 15:231–237

    Google Scholar 

  • Headley A, Guerette R, Shariati A (2017) A field experiment of the impact of body-worn cameras (BWCs) on police officer behavior and perceptions. J Crim Just 53:102–109

    Google Scholar 

  • Heckman J, LaLonde R, Smith J (1999) The conomics and econometrics of active labor market programs. In: Ashenfelter O, Card D (eds) Handbook of labor economics, vol 3. Elsevier, Amsterdam, pp 1865–2097

    Google Scholar 

  • Hedberg E, Katz C, Choate D (2017) Body-worn cameras and citizen interactions with police officers: estimating plausible effects given varying compliance levels. Just Q 34:627–651

    Google Scholar 

  • Hollis S, Campbell F (1999) What is meant by intention to treat analysis? Survey of published randomised controlled trials. Brit Med J 319:670–674

    Google Scholar 

  • Hyland S (2018) Body-worn cameras in law enforcement agencies, 2016. U.S. Deperment of Justice, Bureau of Justice Statistics, Washington

    Google Scholar 

  • Imbens G, Wooldredge J (2009) Some recent developments in the econometrics of program evaluation. J Econ Lit 47:5–86

    Google Scholar 

  • International Association of Chiefs of Police (2014) Body worn cameras: model policy. International Association of Chiefs of Police, Alexandria

    Google Scholar 

  • Jennings W, Lynch M, Fridell L (2015) Evaluating the impact of police officer body-worn cameras (BWCs) on response-to-resistance and serious external complaints: evidence from the Orlando police department (OPD) experience utilizing a randomized controlled experiment. J Crim Just 43:480–486

    Google Scholar 

  • Katz C, Choate D, Ready J, Nuno L (2014) Evaluating the impact of officer worn body cameras in the phoenix police department, center for violence prevention and community safety. Arizona State University, Phoenix, AZ

    Google Scholar 

  • Lafayette Group (2015) Major cities chiefs and major county sheriffs survey of technology needs—body worn cameras. Lafayette Group, Vienna

    Google Scholar 

  • Leuven E, Sianesi B (2003) PSMATCH2: stata module to perform full mahalanobis and propensity score matching, Common support graphing, and covariate imbalance testing. Retrieved from http://ideas.repec.org/c/boc/bocode/s432001.html. Accessed 2 May 2018

  • Lipsey M (1990) Design sensitivity: statistical power for experimental research. Sage Publications, Thousand Oaks

    Google Scholar 

  • Lum C, Koper C, Merola L, Scherer A, Reioux A (2015) Existing and ongoing body worn camera research: knowledge gaps and opportunities, center for evidence-based crime policy. George Mason University, Fairfax

    Google Scholar 

  • Lum C, Stoltz M, Koper C, Scherer A (2019) Research on body-worn cameras: what we know, what we need to know. Criminol Publ Pol 18:93–118

    Google Scholar 

  • MacDonald H (2016) War on cops: how the new attack on law and order makes everyone less safe. Encounter Books, New York

    Google Scholar 

  • Malm A (2019) Promise of police body-worn cameras. Criminol Publ Pol 18:119–130

    Google Scholar 

  • Mathiesen T (1997) The viewer society: michel Foucault’s `panopticon’ revisited. Theoret Criminol 1:215–234

    Google Scholar 

  • Mesa Police Department (2013) On-officer body camera system: program evaluation and recommendations. Mesa Police Department, Mesa

    Google Scholar 

  • Nagin D (2013) Deterrence in the twenty-first century. Crime Just 42:199–263

    Google Scholar 

  • Peterson B, Yu L, La Vigne N, Lawrence D (2018) The Milwaukee Police Department’s Body-Worn Camera Program Urban Institute, Washington

  • Police Executive Research Forum (2014) Implementing a body-worn camera program: recommendations and lessons learned. Office of Community Oriented Policing Services, Washington

    Google Scholar 

  • Police Executive Research Forum (2018) Costs and benefits of body-worn camera deployments. Police Executive Research Forum, Washington

    Google Scholar 

  • Ready J, Young J (2015) The impact of on-officer video cameras on police-citizen contacts: findings from a controlled experiment in Mesa. AZ J Exp Criminol 11:445–458

    Google Scholar 

  • Rosenbaum P, Rubin D (1985) Constructing a control group using multivariate matched sampling methods that incorporate the propensity score. Am Stat 39:33–38

    Google Scholar 

  • Rossi P, Lipsey M, Freeman H (2004) Evaluation: a systematic approach, 7th edn. Sage Publications, Thousand Oaks

    Google Scholar 

  • Rowe M, Pearson G, Turner E (2018) Body-worn cameras and the law of unintended consequences: some questions arising from emergent practices. Policing 12:83–90

    Google Scholar 

  • Rubin D (1980) Randomization analysis of experimental data: the fisher randomization test. J Am Stat Assoc 75:591–593

    Google Scholar 

  • Shadish W, Cook T, Campbell D (2002) Experimental and quasi-experimental designs for general causal inference. Wadsworth, Belmont

    Google Scholar 

  • Sherman L (1990) Police crackdowns: initial and residual deterrence. Crime Just 12:1–48

    Google Scholar 

  • Silver JR, Roche SP, Bilach TJ, Bontrager Ryon S (2017) Traditional police culture, use of force, and procedural justice: investigating individual, organizational, and contextual factors. Just Q 34:1272–1309

    Google Scholar 

  • Silvia P, Duval TS (2001) Objective self-awareness theory: recent progress and enduring problems. Pers Soc Psych Rev 5:230–241

    Google Scholar 

  • Sutherland A, Ariel B, Farrar W, De Anda R (2017) Post-experimental follow-ups– Fade out versus persistence effects: the Rialto police body-worn camera experiment four years on. J Crim Just 53:110–116

    Google Scholar 

  • Tilley N (1993) Understanding car parks, crime, and CCTV: evaluation lessons from safer cities. Home Office, London

    Google Scholar 

  • U.S. Department of Justice (2015) Fact sheet: office of justice programs comprehensive body-worn camera program. U.S. Department of Justice, Washington

    Google Scholar 

  • Wallace D, White M, Gaub J, Todak N (2018) Body-worn cameras as a potential source of depolicing: testing for camera-induced passivity. Criminology 56:481–509

    Google Scholar 

  • Weisburd D (2010) Justifying the use of non-experimental methods and disqualifying the use of randomized controlled trials. J Exp Criminol 6:209–227

    Google Scholar 

  • White M (2014) Police officer body-worn cameras: assessing the evidence. Office of Community Oriented Policing Services, Washington

    Google Scholar 

  • White M, Gaub J, Todak N (2018) Exploring the potential for body-worn cameras to reduce violence in police-citizen encounters. Policing 12:66–76

    Google Scholar 

  • Yokum D, Ravishankar A, Coppock A (2017) Evaluating the effects of police body-worn cameras: a randomized controlled trial. Office of the City Administrator, Washington

    Google Scholar 

  • Zimring F, Hawkins G (1973) Deterrence: the legal threat in crime control. University of Chicago Press, Chicago

    Google Scholar 

Download references

Acknowledgements

This work was supported through research funds provided by the City of Boston and the Rappaport Institute for Greater Boston. The authors would like to thank Mayor Martin Walsh, Police Commissioner William Evans, Superintendent Kevin Buckley, Superintendent Frank Mancini, Superintendent John Daley, Amy Condon, Desiree Dusseault, and Dawn Mello for their support and assistance in the completion of this research report. The conclusions presented here are those of the authors and do not represent the official position of the City of Boston, Boston Police Department, or the Rappaport Institute for Greater Boston.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Anthony A. Braga.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Braga, A.A., Barao, L.M., Zimmerman, G.M. et al. Measuring the Direct and Spillover Effects of Body Worn Cameras on the Civility of Police–Citizen Encounters and Police Work Activities. J Quant Criminol 36, 851–876 (2020). https://doi.org/10.1007/s10940-019-09434-9

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10940-019-09434-9

Keywords

Navigation