Bystander and Security Response

Bystanders and security personnel who are on the scene (including off-duty officers) can do a great deal to prevent casualties and can even stop an attack. Across our cases, bystanders and/or security personnel tried to stop shooters in 65 cases and were successful or partly successful more than 85 percent of the time. They were successful in ending the shooting two-thirds of the time (44 cases) and partly successful (e.g., they got the shooter to flee) another 18 percent of the time (12 cases). Attempts to stop the shooter failed only 14 percent of the time (9 cases).

Using our case analysis, as well as literature reviews, we recommend the following:

Escape or Conceal Yourself, if You Can . . .

Civilian bystanders who can successfully escape from a shooter (i.e., run) or hide without exposing themselves to the shooter's line of fire (or exposing themselves to the line of fire very briefly while escaping) should do so. Our analysis validated the often-heard saying of run, hide, and fight, or avoid, deny, and defend (Advanced Law Enforcement Rapid Response Training [ALERRT], undated a), in that order.

Remember that everyone who tries to disrupt a shooting likely places themselves in the line of fire.

. . . However, It Is "Fight," Not "Duck and Cover."

Those who cannot escape from the line of fire are likely best off attacking and trying to incapacitate the shooter as quickly as possible.

• In our cases, when bystanders took physical action against a shooter, interventions were successful in ending the attack two-thirds of the time or at least partly successful (e.g., bystanders got the shooter to flee) more than 85 percent of the time.
• Use extreme caution when disarming or disabling a shooter. Use the environment—especially any concealment—to your advantage. Do not approach a shooter straight-on if at all possible; avoid frontal charges. Several bystanders have been killed taking this approach; it turns the bystander into a stationary target from the shooter's perspective. To help gain distance, throw whatever is available toward the shooter.
• For the greatest chance of success, groups of bystanders need to work together to take out the shooter. In our preliminary data, groups were unsuccessful in stopping the shooter only one of 19 times. The best approach was to tackle the shooter from multiple directions at once and get them on the ground. This was effective in 12 of 12 attempts.
• Stopping a shooter as a lone bystander is riskier than in a group, but it was still successful half of the time (13 of 25 attempts) and failed in only 20 percent of attempts.

Security Guards and Off-Duty Officers Can Play Key Defense Roles

Trained and armed security personnel and off-duty officers can and have played critical roles in stopping shooters. Our case data showed that they stopped shootings successfully close to 90 percent of the time (they were successful in 17 cases and unsuccessful in just two cases).

However, shooters have sometimes directly targeted armed guards and officers as part of their attacks. Our data include four cases in which guards on the scene were targeted and killed by shooters, with five fatalities resulting.

Armed Defense

Our data include 11 cases in which shooters were stopped by being shot themselves. The majority of these cases (9 of 11) were the result of armed security guards or off-duty officers; there were only two cases of civilian bystanders using firearms.

One does not need a gun to stop a mass shooter. Of the 56 successful or partly successful interventions, 80 percent (45 cases) did not involve armed defense.

De-Escalation and Presence Measures

These measures have occasionally worked (we found three examples in our case analysis). In all three cases, these measures were used by authorities (such as a school principal or school resource officer) with respect to the shooter. De-escalation and presence measures may be an option, but they are extremely risky.

People need to be cognizant of their roles in helping provide security, similar to the ways in which they are cognizant of ensuring fire safety or providing first aid when needed. People need not be overly concerned—as we noted, there are fewer than ten mass attacks per 100 million people per year—but should be vigilant. For example, an usher is typically assigned to greet people, and how the usher might proactively greet someone who is acting suspiciously can provide considerable protection. In a typical interaction, the usher will find out that the person is new and welcome them; however, in the rare circumstance, the usher will discover and protect people from more nefarious intentions.

More Details on Bystander and Security Response

Previous research has highlighted several cases in which bystanders successfully restrained the shooter, either physically or verbally, and stopped an attack. In 13 percent of active shooting incidents from 2000 to 2013 (as reviewed by Blair and Schweit, 2014; and Blair, Sandel, and Martaindale, 2020), the authors found that bystander interventions were associated with decreased casualties.

The following table shows who attempted to act (e.g., lone bystanders, groups of bystanders, or on-scene security guards or off-duty officers) and the specific actions they took. The table also shows the number of cases in which each action occurred and whether the actions were successful in stopping the shooting, partly successful in getting the shooter to withdraw from the scene, or not successful.

Action Taken	Partly Successful	Successful	Unsuccessful	Grand Total
Authority(s) attempted to order shooter to stop			1	1
Authority(s) ordered shooter to stop		2		2
Authority(s) talked down shooter		1		1
Bystander attempted to frontally charge shooter	1		2	3
Bystander attempted to grab weapon	1		1	2
Bystander attempted to shoot but was pinned down under fire			1	1
Bystander attempted to talk down shooter			1	1
Bystander brandished weapon at shooter		2		2
Bystander chased shooter	1			1
Bystander drove into shooter	1	1		2
Bystander grabbed shooter's arm		4		4
Bystander shot shooter		2		2
Bystander tackled shooter	1	4		5
Bystander threw objects at shooter	2			2
Group clubbed shooter	1			1
Group disarmed shooter		1	1	2
Group pushed shooter out of the room	1			1
Group tackled shooter		12		12
Group threw objects at shooter	3			3
Off-duty officer or guard attempted to stop attack by firing at shooter		2		2
Off-duty officer or guard engaged shooter		4		4
Off-duty officer or guard shot shooter		9		9
Off-duty officer or guard tackled shooter		1		1
Off-duty officer or guard tasered shooter		1		1
Grand total	12	46	7	65