A Case Study in Perimeter Failure

By Tucker Bonnevie, Owner of 3 Pillars Consulting LLC, Licensed Private Investigator & Security Consultant

When tragedy strikes at mass gatherings, whether it’s a political rally, a concert, or a sporting event, the public often asks: “How could this happen with so much security present?”

The truth is, in nearly every high-profile incident, the greatest vulnerabilities lie not at the stage or within the controlled inner circle, but along the outer perimeter, the transitional space where crowds meet unsecured terrain.

The Trump Assassination Attempt

In July 2024, former President Donald Trump narrowly survived an assassination attempt at a campaign rally in Butler, Pennsylvania. Despite the presence of the Secret Service and local law enforcement, the shooter managed to position himself outside the inner security zone, using an elevated vantage point on a nearby building.

This was not a failure of inner-ring protection. It was a failure of outer perimeter surveillance, terrain denial, and threat identification.

The Route 91 Harvest Festival

The tragedy at the Route 91 Harvest Festival in Las Vegas in October 2017 remains one of the most devastating reminders of what happens when elevated threat positions are underestimated or left unsecured. In this case, the shooter, Stephen Paddock, utilized a 32nd-floor hotel suite at the Mandalay Bay overlooking the concert grounds. From that vantage point, he was able to rain gunfire down on thousands of unsuspecting attendees, killing 58 people and injuring hundreds more.

Despite extensive inner security measures—bag checks, controlled entry points, visible police presence, these defenses were rendered meaningless by an attacker who positioned himself outside the event’s defined security zone. This demonstrates a critical gap in event security planning: the tendency to focus heavily on the crowd and immediate entry points while neglecting the broader environment that can be exploited by determined adversaries.

The Assassination of Charlie Kirk

The recent killing of Charlie Kirk during a speaking event at Utah Valley University has tragically become another stark example of what can go wrong when outer perimeters and possible threat areas are not adequately identified or monitored.  

What We Know

On September 10, 2025, Charlie Kirk, founder of Turning Point USA, was fatally shot while speaking outdoors at an event at Utah Valley University called “Prove Me Wrong”. There were ~3,000 people in attendance. The shooter fired from a rooftop of a nearby building, estimated to be 200 yards away, using a high-powered bolt-action rifle. Videos of the event show the suspect accessing elevated terrain (stairs/roofs) before the event began. The weapon has been recovered, but the shooter remains at large. 

How This Exemplifies Outer Perimeter Security Gaps

• Unmonitored Elevated Vantage Points

The shooter was able to use a rooftop, a location outside of the venue’s immediate control and likely not covered by the inner security plan. Elevated positions offer clear lines of sight and fire, making them extremely dangerous if not identified and secured.

• Area Beyond Immediate Venue Not Secured

The distance of 200 yards from the vantage point meant the shooter was entirely outside what might have been defined as the “secure zone” around the stage or gathering. Outer areas (nearby buildings, rooftops) were not treated as threat-areas in advance, apparently because they fell outside typical venue boundaries.

• Insufficient Reconnaissance and Terrain Denial

The ability of the shooter to access stairs/roofs before the event suggests no prior site survey or denial of those spaces. In many cases, outer perimeter security fails to include inspection of nearby structures that could be exploited.

• Crowd Size vs. Staffing & Surveillance Coverage

With thousands of attendees, standard security resources may have been stretched; the event was outdoors and large. That amplifies the need for overlapping surveillance, overwatch positions, and external intelligence. But reports indicate there was no effective monitoring of the roof or suppression of external lines of fire.

• Delayed or Insufficient Response to Potential Threats

The shooter’s movements (ascending roofs, accessing vantage points) suggest there may have been windows of time where intervention could have occurred if outer perimeter monitoring or surveillance had been active and linked with rapid response.

Some Reasons Why Outer Perimeters Are Overlooked

• Resource Limitations
  Law enforcement and security teams often face staffing shortages. The bulk of personnel are deployed inside the venue or at immediate entry points, leaving surrounding areas under-monitored.

• Jurisdictional Confusion
  Outer areas may not technically fall under the responsibility of the private security team or federal protection detail, leading to gaps in coverage.

• Overconfidence in Credentialed Access
  Security plans often focus heavily on screening credentialed attendees, neglecting to recognize that the greatest threats may originate outside the credential zone.

• Lack of Real-Time Intelligence Integration
  Outer perimeters require constant monitoring via drones, cameras, overwatch positions, and intelligence sharing. Too often, these layers are missing or siloed.

Lessons & Best Practices

• Pre-Event Site Surveys: Always treat adjacent buildings and high points as part of the operational risk footprint. Survey all structures within a radius equal to likely threat‐range (taking into account firearms that may have long range).

• Outer Perimeter Control Zones: Define outer perimeter zones that extend beyond the venue itself—this might include neighboring rooftops, parking lots, elevated terrain, and any line-of-sight routes.

• Elevated Surveillance Assets: Use drones, high-resolution cameras, and designated overwatch teams to monitor those outer zones continuously throughout the event—before crowd arrival, during the gathering, and for teardown.

• Coordination with Local Authorities: Because many outer perimeter areas are in mixed jurisdiction (public, private, university property, city property), ensure legal access, partnership, and coordination so that outer threat areas can be surveyed or restricted if necessary.

• Rapid Threat Identification & Intervention: Security plans should build in layers so that when somebody is observed in a suspicious elevated position, there is a mechanism (protocols, alarms, response teams) to assess risk and neutralize or deny access.

The Cost of Ignoring Outer Threat Vectors

Recent tragedies and near-tragedies show us that focusing exclusively on inner zones creates blind spots that adversaries can exploit. Attackers understand that outer perimeters are less monitored, offering opportunities to stage, surveil, or launch an assault.

The key lesson from these events is that the outer perimeter of an event extends far beyond the barricades, fencing, or immediate venue footprint. Adjacent structures, particularly those with line-of-sight over large gatherings, must be factored into threat assessments. Hotel windows, rooftops, balconies, and other elevated positions create ideal sniper platforms if left unmonitored or uncontrolled.

The Las Vegas shooting, like the attempted assassination of President Trump and the confirmed assassination of Charlie Kirk, illustrates a consistent and deadly pattern: attackers are not just breaching the gates; they are finding overlooked vantage points. Until security planning evolves to address these outer perimeter threats, mass gatherings will remain vulnerable to the same tragic outcome.

How We Fix This

• Layered Security Planning
  Outer perimeter positions must be treated as mission-critical, not secondary. Elevated positions, wooded areas, parking lots, and surrounding structures should be identified and monitored as part of the primary security plan.

• Intelligence-Led Deployment
  Threat assessments should drive outer ring deployments, with emphasis on known vulnerabilities and surveillance choke points.

• Technology Integration
  Drones, long-range optics, mobile surveillance units, and coordinated communication networks should extend coverage beyond the crowd footprint.

• Shared Responsibility
  Local law enforcement, federal agencies, and private security must collaborate with clearly defined roles for outer perimeter monitoring.

• Public Vigilance – “See Something, Say Something”
  No amount of technology or manpower can replace the eyes and instincts of the public. Attendees, staff, and community members must be empowered and encouraged to report suspicious behavior, unusual activity, or overlooked vulnerabilities. Collective vigilance is one of the strongest tools we have to stop attacks before they happen.

Final Thought

When security professionals fail to identify and secure outer perimeter threat areas, they leave events vulnerable to catastrophic breaches. These blind spots are not accidents; they are predictable weaknesses that attackers are eager to exploit.

As a nation, we cannot wait for the next tragedy to remind us of what’s at stake. Security isn’t just about fences and checkpoints—it’s about protecting lives, families, and communities before danger strikes. True protection doesn’t end at the gate; it begins far beyond it, in the places too often overlooked. If we want our children to grow up without fear, if we want to gather without looking over our shoulders, then we must demand more. Together, through vigilance, preparation, and compassion, we can build a safer tomorrow.