Two hundred and ninety eight police departments were randomly drawn from the U.S. Department of Justice Public Safety Officer Benefits database, Washington, DC. These 298 police departments had experienced officer deaths within the last ten years. The response rate was 100%. Through questionnaires, each department was asked to provide data on the reported number of suicides that occurred over the past ten years for on-duty, off-duty, and retired police officers. Additional information on the location (at worksite vs. away from worksite) and the method used (firearm, knife, hanging or asphyxiation) was available. However, the information on the location and method used was aggregated for each PD and therefore could not be linked to an individual suicide. The total number of police officers in these departments (n = 119,624) was used to create four categories of police department (PD) size: 1) smallest, ≤50 officers; 2) small, 51-200 officers; 3) medium, 201-500 officers; and 4) large, 501-6,500 officers. Annual suicide rates were calculated per 100,000 officers for each PD size category and p-values from Chi-square tests were determined to assess whether the rates were statistically different across these PD size categories. Six pairwise comparisons between the PD size categories were made using Chi-square tests; p-values were multiplied by six to adjust for multiple comparisons using the Bonferroni correction.

Of the 298 police departments, 86 (29%) reported one or more suicides in the past ten years. A total of 189 suicides were reported. Of the 85 PDs who reported information on the location of the suicides, 89% reported that the suicides occurred away from the worksite compared to 11% which occurred at the worksite (Table 1). Of the 81 PDs who reported the method of suicide, firearms were the most frequently reported method (91.4%); other methods included knives, hangings, asphyxiation, drug overdose and automobile (Table 2).

Of the 189 total suicides, 155 (84.7%) were committed by police officers who were employed at the time (10 of these were on-duty suicides (5.5%), 145 were off-duty suicides (79.2%), and 28 (15.3%) were committed by retired police officers. PD size was not reported for six additional off-duty suicides and these suicides were excluded from the analyses.

Annual suicide rates per 100,000 officers were calculated for each PD size category. The overall annual suicide rate was 15.3 per 100,000 officers (Table 3). The annual suicide rate varied significantly across the PD size categories: 43.78/100,000 for officers in the smallest PDs (≤50 officers), 13.67/100,000 for officers in the small PDs (51-200 officers), 26.39/100,000 for officers in the medium PDs (201-500 officers), and 12.46/100,000 for officers in the largest PDs (501-6,500 officers). More specifically, PDs that were smallest (≤50 officers) had significantly higher suicide rates than those classified as small (51-200 officers; p = 0.028) and large (501-6,500 officers; p < 0.0001).

Our results suggest that smaller police departments have a reported higher annual suicide rate than larger departments. A significant difference in the annual suicide rate across department size categories was found. The annual suicide rate for all departments of 15.3/100,000 officers was above the U.S. general population suicide rate of 11/100,000, with the smallest department rate being approximately four times the national rate (43.78/100,000). These results were somewhat surprising, as there is a general consensus that small departments have a sense of teamwork and a stronger sense of personal identity. Size also appears to have a motivating effect (Moates & Kulonda, 1990). These group characteristics would seem to be more protective against suicide, lending to cohesiveness and support in times of stress and trauma (Hogg, 1992.)

Other results in the present study appear to be consistent with previous research. First, retired officers were less likely to commit suicide than currently employed officers (15.3% vs. 84.7%). In general, police officers are more likely to commit suicide while still working. Violanti and colleagues (1998) found the highest risk for suicide centered on 15-20 years of police service just prior to retirement, indicating a period of high anxiety over decisions to remain in police work or retire. Violanti (1983) found that officers in the 12-20 year career category had the highest stress scores, identifying this period as the “disenchantment” stage of police work. Hartley, Violanti, Fekedulegn, Andrew, and Burchfiel (2007) found that officers in this police service range had higher negative life event and depression scores than younger officers. Second, the proportion of off-duty suicides was much higher than on-duty suicides. Violanti (1996), in a comparison of five police departments, found that an average of 64% of suicides occurred away from the department. Campion (2001) found that 100% of suicides committed by officers in small PDs occurred while off-duty. Finally, concerning the method of suicide, the present study found that approximately 91% of officers used a firearm. Similar results have also been found in previous work (Violanti, 1996; Cronin, 1982; Danto, 1978; Campion, 2001).