“Active Shootings,” which include shootings in public, confined areas such as schools, often traumatize communities and attract intense media coverage. Proposed policy responses to the phenomenon, such as concealing information as to casualty counts and even the identities of shooters, often suppose that active shootings are “contagious,” in that previous occurrences can enhance the likelihood of subsequent occurrences. This study marks the first attempt at assessment of the contagiousness of the active shooting phenomenon, and deploys a statistical model—the series hazard model—that is well-suited to the substantive issue of contagion as well as the fine-grained nature of the active shooting data. Results indicate that the hazard of observed active shootings was a function of the number of active shootings that preceded them in the previous two weeks.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Given the relatively small sample size, monthly dummies were avoided in order to limit the number of independent variables in certain models.
In order to avoid dropping the four cases with missing values on age, the mean value (36.80) was imputed.
A word about the “marginal significance” of the “number of active shootings in the last two weeks” contagion variable is perhaps in order. Some scholars prefer to disregard findings of marginal significance while others are willing to substantively interpret such findings, at least under certain conditions. Several reasons can be offered in support of interpreting the marginally significant effect of this variable. First, the present researcher judged that on balance, given the literature review and that active shootings and contagion have heretofore not been studied, it was best to operate with a two-tailed test. Other researchers, however, might quite reasonably disagree and hold that a one-tailed approach should have been adopted—perhaps, for example, because of different perspectives on the literature review, or perhaps because the contagion construct has deep roots in learning theory, which has empirically exhibited noteworthy explanatory power in a wide array of criminological studies.
Second, it might be reasonable to suppose that in view of the magnitude of the impacts active shootings can have on communities together with the amount of resources devoted to the active shooting problem, and the potential effect of policy responses on civil liberties as well as safety, a bright line, summary distinction between p=.07 or .09 and p=.05 is not the best way to proceed. In short, considerations of “practical importance” might justify substantive interpretation of the contagion findings in this study.
In light of the above, interpretation of contagion results is offered, followed by a discussion of the findings regarding the incident characteristics.
Baron JN, Reiss PC (1985) Same time, next year: Aggregate analyses of the mass media and violent behavior. Am Soc Rev 50:347–363
Berkowitz L, Macaulay J (1971) The contagion of criminal violence. Sociometry 34:238–260
Black, J. (1991). The Aesthetics of Murder. A study in romantic literature and contemporary culture. The Johns Hopkins University Press.
Cantor CH, Sheehan P, Alpers P, Mullen P (1999) Media and Mass Homicides. Arch Sui Res 5:283–290
Carcas C, Mouzos J, Grabosky P (2002) The mass murder as quasi-experiment. Hom Stud 6:109–127
Coleman JS (1964) Introduction to Mathematical Sociology. Free Press, New York
Cooper, A. and Smith E.L. (2011). Homicide trends in the United States 1980-2008: Annual Rates for 2009 and 2010. United States Department of Justice, Bureau of Justice Statistics
Dietz PE (1986) Mass, Serial, and Sensational Homicides. Bul New York Acad Med 62:477–491
Dugan L (2011) The series hazard model: An alternative to time series for event data. J Quant Crim 27:379–402
Dugan L (2010) Estimating effects over time for single and multiple units. In: Piquero AR, Weisburd D (eds) Handbook of Quantitative Criminology. Springer Science, New York, pp 741–763
Dugan L, LaFree G, Piquero AR (2005) Testing a rational choice model of airline hijackings. Criminology 43:1031–1066
Fox JA (2009) Mass murder goes to college: An examination of changes on college campuses following Virginia Tech. Am Beh Sci 52:1465–1485
Fox JA (2004) Missing data problems in the SHR: Imputing offender and relationship characteristics. Hom Stud 8:214–254
Fox J, DeLateur MJ (2014) Mass shootings in America: Moving beyond Newtown. Hom Stud 18:125–145
Hamilton LC, Hamilton JD (1983) Dynamics of terrorism. Int Stud Quar 27:39–54
Helfgott, J.B. (2008). Criminal Behavior: Theories, Typologies, and Criminal Justice. Sage Publications, Inc.
Holden RT (1986) The contagiousness of aircraft hijacking. Am J Soc 91:874–904
Holden RT (1987) Time series analysis of a contagious process. J Am Stat Assoc 82:1019–1026
Huff-Corzine, L., McCutcheon, J.C., Corzine, Jarvis, J.P., Tetzlaff-Berniller, M.J., Weller, M. and London, M. (2014). Shooting for accuracy: Comparing data sources on mass murder. Hom. Stud. 18: 105--124.
Kelly, R.W. (2012). Active Shooter: Recommendations and analysis for risk mitigation. New York City Police Department.
Kelly PJ, Lim LY (2000) Survival analysis for recurrent event data: An application to childhood infectious diseases. Stat Med 19:13–33
LaFree G, Dugan L, Korte R (2009) The impact of British counterterrorist strategies on political violence in Northern Ireland: Comparing deterrence and backlash models. Criminology 47:17–46
Levin J, Madfis E (2009) Mass murder at school and cumulative strain. Am Beh Sci 52:1227–1245
Meloy JR, Hempel AG, Gray BT, Mohandie K, Shiva A, Richards TC (2004) A comparative analysis of North American adolescent and adult mass murderers. Beh Sci and the Law 22:291–309
Phillips D (1983) The impact of media violence on U.S. homicides. Am Soc Rev 48:560–568
Riedel M, Regoeczi WC (2004) Missing data in homicide research. Hom Stud 8:163–192
Savage J (2004) Does viewing violent media really cause criminal violence? A methodological review. Aggress Violent Behav 10:99–128
Schmidtke A, Schaller S, Miller L (2002) Imation[sic] of amok and amok-suicide. Kritz Dergisi 10:49–60
Schulman, A. N. (2013, November 8). What mass killers want—and how to stop them. 2013. Wall Street Journal The Saturday Essay. Retrieved from http://wsj.com/articles/SB10001424052702303309504579181702252120052
Stack S (1989) The effect of publicized mass murders and murder-suicides on lethal violence, 1968-1980. Soc Psy Psych Epidem 24:202–208
Surette R (2013) Cause or catalyst: The interaction of real world and media crime models. Am J Crim Justice 38:392–409
Surette R (2002) Self-reported copycat crime among a population of serious and violent juvenile offenders. Crime and Del 48:46–69
Swanson SA, Colman I (2013) Association between exposure to suicide and suicidality outcomes in youth. Can Med Assoc J 185:870–877
United States Department of Homeland Security. (2008). Active shooter: How to respond. http://www.dhs.gov/xlibrary/assets/active_shooter_booklet.pdf
About this article
Cite this article
Kissner, J. Are Active Shootings Temporally Contagious? An Empirical Assessment. J Police Crim Psych 31, 48–58 (2016). https://doi.org/10.1007/s11896-015-9163-8
- Active Shootings
- Active Shooters
- Series Hazard Model