Public spaces are the shared ground of civic life. Parks, streets, plazas, transit stops, and community centers are open by design. That openness is their purpose. It is also their exposure. These places have large footprints, dense crowds, many entry points, and few physical barriers. That makes them hard to secure.

The data confirm the concern. Open spaces are now the single most common setting for active shooter attacks. In 2024 they accounted for half of all such incidents recorded by the FBI.

This paper is written for two audiences: security professionals who protect public places, and the civic leaders who steward them. It has three goals. First, to set out what the data show. Second, to describe prevention approaches that are supported by evidence. Third, to explain how modern situational-awareness technology, including AI weapon detection, fits inside a broader plan.

The core message is simple. Safety in open spaces does not come from a wall or a single guard. It comes from layers that work together: good design, visible presence, fast detection, clear communication, and a practiced response. Technology strengthens detection. It does not replace people, planning, or community trust.

THE THREAT: WHAT THE DATA SHOW

Open spaces are the most common target

The FBI tracks active shooter incidents by location. From 2020 to 2024 it recorded 223 such incidents. Open spaces accounted for 73 of them, more than any other category. In 2024, open spaces made up 50 percent of all incidents.

The overall picture is improving but remains serious. The FBI counted 24 active shooter incidents in 2024, a 50 percent drop from 2023. Those 2024 incidents still killed 23 people and wounded 83.

Everyday community gun violence

Mass-casualty attacks are the most visible threat, but they are a small share of the total. The United States records more than 44,000 firearm deaths a year.

Most of that harm is not a mass shooting. In recent CDC data, roughly 58 percent of gun deaths were suicides and about 38 percent were homicides. Much of the homicide total happens outdoors, on streets and in public places, and shapes how safe a community feels.

By a broader definition, incidents in which four or more people are shot, the Gun Violence Archive counted about 500 mass shootings in 2024, down from a peak near 690 in 2021.

These numbers point to one conclusion. Public-space safety is not only about preventing rare attacks. It is also about reducing the routine violence that erodes trust in shared places.

Why open spaces are hard to protect

Open environments share features that raise risk:

● Large areas and constant movement make full awareness difficult. ● Dense, fast-moving crowds are hard to screen or restrict. ● Many entry points and few barriers give an attacker freedom to move. ● The surrounding area, parking lots, approaches, and transit stops, often gets less attention than the core, yet is where early warning signs appear.

One fact drives everything. An attack may unfold in seconds, but it is rarely spontaneous. There are usually minutes beforehand when a threat is present or approaching. Noticing that window early is what changes the outcome.

A LAYERED APPROACH TO PREVENTION

Federal guidance and security research agree on one idea: layered security. No single layer is perfect. Each buys time and raises the chance a threat is stopped or reduced. For public spaces, five layers matter most.

1. Design the environment

The built environment is the first and cheapest layer. Crime Prevention Through Environmental Design (CPTED) shapes space to improve sightlines, reduce blind spots, guide movement, and signal that a place is cared for and watched. The evidence is strong, including from randomized trials.

● Lighting works. A randomized study in New York City found that adding street lighting cut nighttime outdoor crime by at least 36 percent. ● Maintaining land works. A citywide randomized trial in Philadelphia found that cleaning and greening vacant lots reduced shootings, with gun-violence reductions near 29 percent in the poorest neighborhoods. ● Upkeep matters. Broader reviews link greening, clean-up, and visible maintenance to lower assault and gun-assault rates, though effects can fade without upkeep.

Design is not a substitute for security. But it lowers opportunity, and it does so for every hour of every day.

2. Visible presence

A visible security presence deters attackers and speeds intervention. This includes uniformed patrols, mobile units, event staff, and trained ambassadors who know the space. In large open areas, human observation alone cannot see everything. Presence works best when paired with the layers below.

3. Detect

Detection shortens the gap between when a threat appears and when the response begins. In open spaces, detection layers include:

● Trained staff and community members who know the warning signs and how to report them. ● Video surveillance that is actively monitored, not just recorded for later review. ● AI-powered video analytics that watch every camera feed at once and flag a visible weapon or anomalous behavior in real time.

Cameras record events but do not interpret them. A human operator cannot watch dozens of feeds for hours without missing something. This is the specific gap that AI detection is built to close.

4. Communicate and coordinate response

Detection has value only if it leads to action. A strong plan connects the alert to the people who can act:

● Fast, clear alerts to on-site security and designated leaders at the same instant. ● Links to public-address systems and mass-notification tools to warn the public. ● Direct lines to local law enforcement and emergency services, with the location and a description. ● The ability to trigger practiced actions such as lockdowns, evacuations, or rerouting crowds without delay.

5. Plan, train, and partner

A plan on paper is not a plan until it is practiced. CISA recommends a simple cycle for public places: connect with local responders, plan policies and procedures, train staff and volunteers, and report suspicious activity.

CISA offers free resources for this work, including its Securing Public Gatherings guidance and the Security of Soft Targets and Crowded Places Resource Guide. Protective Security Advisors can also assess a site at no cost.

● A written emergency action plan covering active threats, medical emergencies, and evacuation. ● Clear, assigned roles for staff, volunteers, and contracted security. ● Regular drills, so people act from memory under stress. ● Trauma supplies and staff trained in Stop the Bleed techniques. ● A recovery plan, including counseling and communications, for after an incident.

TECHNOLOGY’S ROLE: AI DETECTION AND SITUATIONAL AWARENESS

Most public spaces already own the foundation for modern detection: security cameras. The problem is that cameras usually record events without interpreting them. Footage is reviewed after an incident, not during it. AI-powered detection changes that equation, and it is well suited to large, open environments where security can no longer begin at a single entrance.

Closing the detection window

In most attacks the weapon becomes visible in the moments before or during the first shots. That creates a short but real window to act. Because half of active shooter incidents now occur in open spaces, the ability to see a threat outside the building, in a plaza, lot, or approach, is where early intervention makes the difference.

Several vendors now offer AI weapons and behavior detection. These tools analyze live video and alert staff when a firearm is visible or behavior turns dangerous. Civic buyers should evaluate options on accuracy, false-alarm rate, integration, independent testing, and privacy safeguards. Scylla is one such option, and its open-spaces framework illustrates what the technology can do inside a layered plan.

How AI detection supports open spaces

Scylla Gun Detection System runs on top of existing cameras. The system watches every connected feed continuously, flags a visible firearm or anomalous movement, and sends an alert with the camera location, a timestamp, and an image. Smart filtering keeps false alarms very low, so operators receive focused warnings instead of watching a wall of screens.

Key characteristics reported by Scylla include:

● Real-time detection of visible firearms across many cameras at once, including fixed, PTZ, and mobile units. ● Contextual analysis that separates normal activity from genuine threats to reduce false alarms. ● Integration with common video management systems, public-address, and alarm systems, so a site need not replace what it owns. ● Human-in-the-loop design: the system flags potential threats; trained people verify each alert and decide what to do.

The technology has limits that matter for planning. It detects visible threats, not concealed weapons or intent. It is a detection layer, not a shield. Its value comes from linking the detect, communicate, and respond layers into one motion: a threat appears, the system sees it, staff are warned, the public is alerted, and responders move, all in the seconds that decide the outcome.

FUNDING AND PARTNERSHIPS

Cost is a common barrier, but public spaces are rarely secured by one budget alone. Effective programs braid several sources and partners:

● Municipal capital and parks budgets for lighting, landscaping, and maintenance, the highest-return design measures. ● State and local public-safety grants for cameras, analytics, and staffing. ● The federal Nonprofit Security Grant Program, available to eligible nonprofits, including many community centers, for security equipment, training, and planning. ● Community violence intervention funding, which pairs place-based design with outreach and services.

Free federal help is also available. CISA provides no-cost assessments, planning tools, and training for public gatherings and crowded places. Congregating these resources early, and involving a security professional, strengthens both the plan and any grant application.

BALANCING OPENNESS, PRIVACY, AND SECURITY

Public spaces exist to be open, free, and welcoming. Security that feels like a checkpoint can undermine the civic life it is meant to protect. For civic leaders, the goal is safety that preserves the character of the place.

Two principles help. First, favor measures that are quiet and dual-use. Good lighting, clear sightlines, well-kept grounds, and attentive staff improve daily experience as well as safety. Second, treat surveillance technology with care. Set clear policies on what is collected, how long it is kept, who can access it, and how it is audited. Systems that flag a visible weapon and store data only on an alert, rather than tracking every person, are easier to reconcile with privacy and civil liberties.

Community trust is itself a security asset. Residents who feel respected are more likely to report concerns, cooperate with staff, and use the space. Transparency about why measures exist, and limits on how they are used, protects both people and the public realm.

KEY RECOMMENDATIONS

● Start with design. Invest first in lighting, sightlines, and maintenance; the evidence and the return are strongest here. ● Assess the whole footprint. Include parking, approaches, and transit stops, not just the core, using a free CISA or law-enforcement assessment. ● Add a visible presence. Use patrols, event staff, and trained ambassadors who know the space. ● Layer detection. Actively monitor cameras and consider AI weapon detection to watch every feed in real time. ● Connect detection to response. Wire alerts to your team, public-address, and local responders so a warning triggers action in seconds. ● Plan, train, and drill. Adopt CISA’s connect–plan–train–report cycle and rehearse at least twice a year. ● Protect privacy. Set clear policies on data collection, retention, access, and audit before deploying surveillance. ● Braid the funding. Combine municipal budgets, state and local grants, the Nonprofit Security Grant Program, and violence-intervention dollars.

SOURCES

Full citations appear in the footnotes throughout this document. Primary references:

1. FBI — Active Shooter Incidents in the United States in 2024

2. CDC — Firearm Injury and Death: Fast Facts

3. Pew Research Center — What the data says about gun deaths in the U.S.

4. Gun Violence Archive

5. NIJ CrimeSolutions — Street Lighting in NYC Public Housing (randomized trial)

6. Branas et al. — Remediating Blighted Vacant Land on Shootings (citywide RCT, 2018)

7. Vital City — Crime and the Built Environment (CPTED evidence review)

8. CISA — Securing Public Gatherings / Soft Targets and Crowded Places

9. Scylla — Layered Security Framework for Open Spaces / Gun Detection