Levels and Changes in Defensive Firearm Use by US Crime Victims, 1987‒2021

Abstract

Objectives. To examine levels and temporal changes in the frequency of defensive gun use by US crime victims.

Methods. We computed national-level counts of criminal incidents involving firearm defense during 3 periods: 1993 to 2005, 2007 to 2015, and 2016 to 2021. We also considered earlier national estimates for 1987 to 1990. The data came from the US Bureau of Justice Statistics National Crime Victimization Survey (NCVS). We counted firearm defenses as incidents in which victims used a gun to threaten or attack an offender.

Results. Over the 4 periods, for all crimes, victims reported gun defenses in an average range of between 61 000 and 65 000 incidents per year. This included between 38 000 and 53 000 personal (violent) incidents and between 12 000 and 23 000 household (property) incidents.

Conclusions. Firearm defenses occurred at a relatively low and nearly constant level over the 35-year period. Although some victims use guns for defense, these uses are infrequent compared with the incidence of crime.

Public Health Implications. The continuing relative rarity of NCVS armed defenses suggests that claims about the protective benefits of widespread firearm ownership may be overstated. (Am J Public Health. 2024;114(12):1384–1387. https://doi.org/10.2105/AJPH.2024.307838)

How often crime victims use guns for self-defense is an issue in firearm policy research. General gun ownership carries well-documented social costs, including deaths and injuries from criminal misuse.^1,2 Yet armed victims may avoid personal harms, and guns may help deter would-be offenders.^2,3 Opponents of measures that might affect firearm access stress these possibilities and argue that armed defenses occur as often as several million times each year.^3,4

Multiple estimates of the frequency of defensive gun use exist, but most of these are 20 to 30 years old.^2,3 The estimates also come from cross-sectional analyses, and methodological differences limit comparisons between them. Few studies present recent data, and none, to our knowledge, examine changes in firearm defenses over time.

We used the National Crime Victimization Survey (NCVS) to examine the frequency of defensive gun use. The NCVS provides annual estimates of the incidence of crime in the United States, and its core methodology has remained constant over time.^5,6 Our goal was to update earlier NCVS estimates of firearm defense and to assess temporal variations.

METHODS

The NCVS uses a multistage probability sample of US housing units. The US Census Bureau conducts the survey for the US Bureau of Justice Statistics (BJS). In 2021, the sample consisted of about 150 000 housing units, occupied by 240 000 persons. Housing units remain in the NCVS for 3.5 years, and, at 6-month intervals, residents aged 12 years or older answer screening questions about their experiences with crime. Respondents who report attempted or completed victimizations provide additional details. The NCVS collects information on personal crimes (rape, robbery, assault, and personal larceny) and household crimes (burglary and trespassing, household larceny, and motor vehicle theft).⁶

If victims say that they saw an offender, NCVS interviewers ask, “Did you do anything with the idea of protecting yourself or your property while the incident was going on?” If respondents report no protective actions, interviewers rephrase the question and ask it again. Respondents who offer positive responses next describe what they did. The interviewers code the descriptions into categories that include “attacked offender with gun; fired gun” and “threatened offender with gun.”⁵

Our estimates are incident counts, weighted to represent the population at risk.⁶ The estimates for personal crimes represent the resident noninstitutional population of the United States, aged 12 years or older. The estimates for household crimes represent US housing units. We computed standard errors for the estimates using the BJS’s generalized variance formulas.⁶

As we show in the Results section, firearm defenses are rare, making annual estimates highly variable. To increase stability, we aggregated incidents into 3 periods: 1993 to 2005, 2007 to 2015, and 2016 to 2021. We selected these aggregations partly because they contain many sample cases and partly because they align with changes in the survey. Budget-related modifications in data collection and sample revisions following the 2000 Census produced anomalous 2006 estimates.⁶ The BJS recommends against using the 2006 data, and breaking the series after 2005 allows its exclusion. Another series break occurred in 2016, with changes to sample sites and interview staff based on the 2010 Census.⁶

Besides 1993 to 2021, we also included previously published estimates covering 1987 to 1990.⁷ These use an earlier version of the survey, before the BJS revised the screening questions to encourage more reports. The sample designs and question structures are almost identical across the versions, however, and with cautious interpretations, the earlier estimates supply useful information.

RESULTS

Period-specific estimates of defensive gun use appear in Table 1. Since most defenses involve personal crimes, the table presents both total estimates and separate estimates for personal and household offenses. Assuming an even annual distribution of incidents within aggregations, total defenses ranged between about 61 000 and 65 000 per year, giving an impression of near-constancy over the 35-year period.

TABLE 1—

Estimates of Number of Self-Defensive Firearm Incidents, All Crimes, Personal Crimes, and Household Crimes, Using National Crime Victimization Survey Data: United States, 1987‒2021

Period	Total Firearm Defense Incidents for Period, No. (SE)	Mean Firearm Defense Incidents per Year	Percentage of All Criminal Incidents With Firearm Defense
All crimes
1987–1990	258 460 (41 012)	64 615	0.18
1993–2005	850 617 (85 674)	65 432	0.21
2007–2015	550 379 (62 558)	61 153	0.30
2016–2021	391 312 (56 432)	65 219	0.39
Personal crimes only
1987–1990	192 539 (32 394)	48 135	0.83
1993–2005	692 310 (33 255)	53 255	0.73
2007–2015	340 968 (35 552)	37 885	0.81
2016–2021	262 213 (30 438)	43 702	1.04
Household crimes only
1987–1990	65 921 (18 107)	16 480	0.05
1993–2005	158 307 (17 810)	12 177	0.05
2007–2015	209 311 (35 849)	23 257	0.13
2016–2021	129 099 (21 929)	21 516	0.17

Source. 1987–1990 estimates were adapted from Table 1 from McDowall and Wiersema⁷ and use a different version of the survey than do the others.

Similar results appear after separating personal and household crimes. These estimates are more variable, but in all periods, armed defenses occurred with roughly similar frequencies. Victimizations have decreased in the NCVS overall, slightly raising the proportion of defensive incidents. The proportions are nevertheless uniformly small, exceeding 1% of personal incidents in 2016 to 2021 and falling below 1% for the other aggregations.

DISCUSSION

Between 1987 and 2021, the NCVS yields a stable estimate of about 61 000 to 65 000 defensive gun incidents per year. One should not dismiss firearms as a defense against crime, but armed defenses are infrequent compared with the total volume of offenses or the subset of offenses involving guns. In the 3 periods between 1993 and 2021, the NCVS produces an estimate of 13 062 630 nonfatal firearm crimes. This is 7.3 times larger than our estimate of 1 792 308 armed defenses during the same interval.

Over the analysis period, many states have relaxed laws against carrying guns or have enacted “stand your ground” laws to support resistance against criminal attacks.^8,9 Also during this period, however, opportunities for armed defenses have decreased. Personal victimizations fell from 79.8 per 1000 (in 1993) to 16.5 per 1000 (in 2021), and household victimizations decreased from 322 to 90.3 per 1000.⁶ These lower rates may offset any effects of policies that encourage gun use.

The NCVS is not the only source of information about armed defense, and private surveys provide estimates of its frequency that range from 600 000 to 6.1 million incidents annually.³ The source of the divergence from the NCVS is a longstanding issue, and extensive discussions of the matter exist in the research literature.^1,2 The Appendix (available as a supplement to the online version of this article at https://ajph.org) summarizes the debate.

Although opinions vary, one explanation of the difference lies in the questions that the surveys pose. The NCVS asks about defense only after respondents have reported an attempted or completed crime. Although the other surveys differ in their exact question wordings, all ask a variation on the following: “Have you yourself or another member of your household used a gun, even if it was not fired, for self-protection or for the protection of property at home, work, or elsewhere?”

This question asks about gun use without first establishing the existence of a criminal act, and it relies on respondents’ perceptions of intent. It allows respondents to include gun uses to forestall perceived imminent victimizations, and these may sometimes amount to crimes themselves.

A National Academy of Sciences report on the matter characterized the NCVS and non-NCVS questions as different definitions of defense: “as a response to victimization or as a means to prevent victimization from occurring in the first place.”^2(p102) In line with this difference, survey experiments find that the non-NCVS questions generate many more gun use reports than does the NCVS approach.^10,11 A limitation of the NCVS is that it does not directly ask respondents about gun use, instead recording it when they describe it as a response to victimization. This feature aside, we believe that the NCVS better aligns with common understandings of self-defense.

PUBLIC HEALTH IMPLICATIONS

Self-defense against crime is the major stated reason for US gun ownership.¹² Crime victims do use firearms for defense, and, as measured by the NCVS, the frequency of defense has been steady over the last 35 years. Yet, also according to the NCVS, gun defenses are rare compared against the volume of crime. This suggests caution in accepting claims of millions of firearm defenses per year.