Skip to main content
NCBI home page
JAMA Network logoLink to JAMA Network
. 2023 Jul 26;6(7):e2325868. doi: 10.1001/jamanetworkopen.2023.25868

Characterization of Mass Shootings by State, 2014-2022

Leslie M Barnard 1,✉, Erin Wright-Kelly 2, Ashley Brooks-Russell 2, Marian E Betz 3
PMCID: PMC10372703  PMID: 37494046

Abstract

This case series investigates the rates of mass shootings, along with injuries and deaths, by US state and shooting type.

Introduction

The US has more than 10 times the number of mass shooting events as other developed countries.1 Mass shootings in the US have increased in frequency, with more than half occurring since the year 2000.2 These events have a direct toll on individuals injured or killed, as well as a psychological impact on families, friends, and society.3

Little research has examined the types and distribution of mass shooting events across the US.4 A geographic analysis by type may inform if specific events have disproportionately occurred in particular states or regions of the US. This may generate hypotheses about the contextual (policy, environmental, or sociocultural) factors that may be associated with the distribution of types of mass shooting events and may suggest recommendations for tailored prevention. The purpose of this study was to examine state rates of mass shooting event types and total injuries and deaths in the US.

Methods

The Gun Violence Archive, a database mostly used for research,5 defines a mass shooting as an incident with 4 or more individuals shot or killed, not including the shooter. This case series used data from a 9-year period (January 1, 2014, to December 31, 2022) to calculate cumulative incidence rates of mass shooting event types based on incident characteristics (Figure) and the total number of individuals injured and killed per 1 000 000 people. We also calculated state-level counts and rates for the most common event types. Rates were calculated using population estimates from the US census from 2014 to 2022 and displayed on state-level heat maps.

Figure. Cumulative Incidence of Mass Shootings, 2014-2022.

Figure.

Open in a new tab

Heat maps are presented of the cumulative incidence rate of mass shootings and injuries and deaths from mass shootings by state, 2014 to 2022. Subcategories were gang or drug involvement, armed robbery, carjacking, murder or suicide, and home invasion for crime-related events; domestic violence, family annihilation, kidnapping, or involving a child for domestic violence–related events; bar or club and house party for social-related events; and terrorism, spree shooting, hate crimes, and others for other events.

Results

From 2014 to 2022, there were 4011 mass shootings, ranging from zero events in Hawaii and North Dakota to 414 events in Illinois. For these 9 years, one-third (27.3%) were social-related mass shootings, 15.8% were crime related, 11.1% were domestic violence (DV) related, 1.4% were school or work related, and 52.0% were not a part of these categories (Table). There was a median of 45 mass shootings per state for all states and the District of Columbia (mean, 78.6). A total of 21 006 people were killed or injured (Table).

Table. Incidence of Mass Shootings, Deaths, and Injuries, 2014-2022.

State Population, No.a Mass shooting type Total injuries and deaths
Total Crime related DV related Social related Other
No. Rateb No. Rateb No. Rateb No. Rateb No. Rateb No. Rateb
AL 44 378 527 103 2.32 11 0.25 13 0.29 31 0.70 51 1.15 505 11.38
AK 6 622 309 5 0.76 0 0.00 1 0.15 2 0.30 2 0.30 24 3.62
AZ 63 785 927 45 0.71 9 0.14 6 0.09 19 0.30 14 0.22 249 3.90
AR 27 052 194 44 1.63 7 0.26 7 0.26 10 0.37 23 0.85 257 9.50
CA 352 688 428 367 1.04 79 0.22 36 0.10 98 0.28 193 0.55 1874 5.31
CO 50 837 935 60 1.18 5 0.10 6 0.12 21 0.41 28 0.55 327 6.43
CT 32 316 813 28 0.87 7 0.22 0 0.00 12 0.37 10 0.31 138 4.27
DE 8 734 043 19 2.18 2 0.23 7 0.80 7 0.80 5 0.57 85 9.73
DC 6 137 207 64 10.43 2 0.33 2 0.33 1 0.16 60 9.78 321 52.30
FL 190 016 591 237 1.25 35 0.18 30 0.16 59 0.31 129 0.68 1345 7.08
GA 94 517 232 155 1.64 32 0.34 20 0.21 45 0.48 68 0.72 769 8.14
HI 12 863 400 0 0 0 0 0 0 0 0 0 0 0 0
ID 15 912 416 2 0.13 2 0.13 0 0 0 0 0 0 11 0.69
IL 114 792 734 414 3.61 59 0.51 27 0.24 80 0.70 260 2.26 2073 18.06
IN 60 357 532 85 1.41 16 0.27 8 0.13 33 0.55 34 0.56 422 6.99
IA 28 395 696 18 0.63 2 0.07 2 0.07 12 0.42 5 0.18 92 3.24
KS 26 266 712 22 0.84 5 0.19 0 0 13 0.49 6 0.23 122 4.64
KY 40 185 945 48 1.19 4 0.10 5 0.12 11 0.27 28 0.70 244 6.07
LA 41 834 823 179 4.28 23 0.55 18 0.43 37 0.88 108 2.58 917 21.92
ME 12 134 108 3 0.25 1 0.08 2 0.16 0 0 1 0.08 14 1.15
MD 54 563 993 120 2.20 14 0.26 8 0.15 12 0.22 91 1.67 563 10.32
MA 61 982 752 34 0.55 6 0.10 3 0.05 12 0.19 16 0.26 162 2.61
MI 89 897 371 129 1.43 14 0.16 13 0.14 38 0.42 70 0.78 618 6.87
MN 50 406 473 49 0.97 11 0.22 4 0.08 10 0.20 29 0.58 258 5.12
MS 26 760 340 78 2.91 12 0.45 12 0.45 32 1.20 26 0.97 398 14.87
MO 55 082 568 126 2.29 12 0.22 17 0.31 25 0.45 75 1.36 609 11.06
MT 9 591 297 4 0.42 2 0.21 0 0 1 0.10 1 0.10 19 1.98
NE 17 346 302 15 0.86 2 0.12 1 0.06 4 0.23 8 0.46 79 4.55
NV 27 119 354 31 1.14 7 0.26 4 0.15 10 0.37 13 0.48 657 24.23
NH 12 235 284 1 0.08 0 0 0 0 0 0 1 0.08 4 0.33
NJ 81 058 390 93 1.15 9 0.11 5 0.06 15 0.19 67 0.83 459 5.66
NM 18 900 254 24 1.27 8 0.42 5 0.26 9 0.48 7 0.37 115 6.08
NY 177 155 566 186 1.05 26 0.15 12 0.07 61 0.34 101 0.57 910 5.14
NC 92 971 556 115 1.24 17 0.18 16 0.17 38 0.41 52 0.56 561 6.03
ND 6 857 698 0 0 0 0 0 0 0 0 0 0 0 0
OH 105 197 605 153 1.45 21 0.20 22 0.21 66 0.63 59 0.56 807 7.67
OK 35 518 477 29 0.82 7 0.20 6 0.17 7 0.20 12 0.34 139 3.91
OR 37 353 493 22 0.59 6 0.16 1 0.03 7 0.19 10 0.27 121 3.24
PA 115 724 473 191 1.65 12 0.10 20 0.17 37 0.32 130 1.12 927 8.01
RI 9 629 156 4 0.42 1 0.10 0 0 1 0.10 2 0.21 22 2.28
SC 45 535 409 103 2.26 20 0.44 11 0.24 46 1.01 37 0.81 550 12.08
SD 7 896 125 4 0.51 3 0.38 2 0.25 0 0 0 0 20 2.53
TN 61 033 316 124 2.03 21 0.34 12 0.20 31 0.51 67 1.10 621 10.17
TX 257 089 529 270 1.05 60 0.23 44 0.17 87 0.34 103 0.40 1560 6.07
UT 28 424 830 6 0.21 3 0.11 2 0.07 1 0.04 1 0.04 30 1.06
VT 5 683 707 1 0.18 0 0 1 0.18 0 0 0 0 4 0.70
VA 76 560 754 97 1.27 15 0.20 19 0.25 27 0.35 43 0.56 493 6.44
WA 67 325 769 45 0.67 17 0.25 6 0.09 14 0.21 13 0.19 215 3.19
WV 16 288 106 5 0.31 1 0.06 2 0.12 2 0.12 1 0.06 25 1.53
WI 52 374 030 53 1.01 7 0.13 9 0.17 12 0.23 27 0.52 267 5.10
WY 5 226 119 1 0.19 1 0.19 0 0 0 0 0 0 4 0.77
Total 2 938 620 668 4011 1.36 636 0.22 447 0.15 1096 0.37 2087 0.71 21 006 7.15
Mean (SD) 57 620 013 79 (91.4) NA 12 (15.9) NA 9 (9.8) NA 21 (24.1) NA 41 (52.5) NA 412 (473.5) NA
Median (IQR) 40 185 945 45 (6-124) NA 7 (2-17) NA 6 (1-13) NA 12 (2-37) NA 23 (2-67) NA 257 (30-618) NA
Open in a new tab

Abbreviation: NA, not applicable.

a

Columns may not add up to total owing to overlapping categories. Populations are based on US Census estimates from 2014 to 2022.

b

All rates are per 1 000 000 individuals.

The rate of mass shootings per 1 000 000 people was highest in the District of Columbia (10.4 shootings), followed by much lower rates in Louisiana (4.2 mass shootings) and Illinois (3.6 mass shootings), the states with the next 2 highest rates (Table). Geographical analysis of mass shooting events showed clustering around the southeast region of the US and Illinois (Figure). Crime-, social-, and DV-related mass shootings followed a similar pattern, while mass shootings that were not part of these categories were more evenly distributed across the US.

Discussion

This case series examined the number and rate of mass shooting events (including injuries and deaths) by type of event and US state differences. While results demonstrated state-level differences in rates of mass shootings, findings were limited given use of 1 database with a broad definition of mass shootings. Definitions that include only deaths or events not associated with crime or only indiscriminate mass public shootings may produce different results.6 Future research should assess socioeconomic, political, cultural, and demographic factors that may be associated with incidents of mass shootings across states and address how state policies, contextual factors, and social determinants of health may be associated with mass shooting incident types.

This study of mass shootings examined the burden of and geographic differences between types of mass shootings in the US. The most common specific event type was crime-related mass shootings. Crime-, social-, and DV-related mass shootings followed a similar pattern, with clustering around the southwest. These findings should be used to inform research and state-level prevention strategies.

Supplement.

Data Sharing Statement

Click here for additional data file. (109.9KB, pdf)

References

  • 1.Silva JR. Global mass shootings: comparing the United States against developed and developing countries. Int J Comp Appl Crim Justice. 2022:1-24. doi: 10.1080/01924036.2022.2052126 [DOI] [Google Scholar]
  • 2.Public mass shootings: database amasses details of a half century of U.S. mass shootings with firearms, generating psychosocial histories. National Institute of Justice. Accessed March 24, 2023. https://nij.ojp.gov/topics/articles/public-mass-shootings-database-amasses-details-half-century-us-mass-shootings
  • 3.Lowe SR, Galea S. The mental health consequences of mass shootings. Trauma Violence Abuse. 2017;18(1):62-82. doi: 10.1177/1524838015591572 [DOI] [PubMed] [Google Scholar]
  • 4.Donnelly M, Grigorian A, Inaba K, et al. Trends in mass shootings in the United States (2013-2021): a worsening American epidemic of death. Am J Surg. 2023;S0002-9610(23)00131-9. doi: 10.1016/j.amjsurg.2023.03.028 [DOI] [PubMed] [Google Scholar]
  • 5.Fowler KA, Leavitt RA, Betz CJ, Yuan K, Dahlberg LL. Examining differences between mass, multiple, and single-victim homicides to inform prevention: findings from the National Violent Death Reporting System. Inj Epidemiol. 2021;8(1):49. doi: 10.1186/s40621-021-00345-7 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Booty M, O’Dwyer J, Webster D, McCourt A, Crifasi C. Describing a “mass shooting”: the role of databases in understanding burden. Inj Epidemiol. 2019;6(1):47. doi: 10.1186/s40621-019-0226-7 [DOI] [PMC free article] [PubMed] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supplement.

Data Sharing Statement

Click here for additional data file. (109.9KB, pdf)

Articles from JAMA Network Open are provided here courtesy of American Medical Association

RESOURCES