Pulse Nightclub: The Security Guard Killer with a Trail of Red Flags

Tragically, Omar Mateen was a security guard employed by G4S. He was off-duty on June 12, 2016, when he killed 49 clubgoers at Pulse Nightclub in Orlando Florida, injuring many more. Omar Mateen had a history of FBI investigation after falsely claiming to be associated with multiple terrorist groups. During these investigations, and through other incidents and complaints about Mateen, he continued to be employed by his security firm employer, with no further psychological evaluation.


Omar Mateen had allegedly previously been interviewed by the Federal Bureau of Investigation (FBI) in 2013 and 2014 after reports of extremist behaviour and connections to terrorism. Mateen had falsely claimed to be associated with the Boston marathon bombers, in addition to claiming connection to both Al Qaeda and Hezbollah. However, these allegations were determined to be insubstantial. Throughout these FBI investigations, Mateen was still allowed to work at G4S.

Mateen was allegedly only psychologically evaluated once at the start of his employment with G4S, and not again once the company was put on notice that he had been interviewed by the FBI.

One of Mateen´s former co-workers alleged that he “saw it coming” based on Mateen´s behaviour, which involved talking about killing people “all the time,” and always being angry. Allegedly, Mateen made it clear he did not like “blacks, women, lesbians, and jews.” The former co-worker allegedly complained multiple times to G4S about these comments, and ultimately quit his job due to harassment from Mateen. G4S continued to employ Mateen, who obtained a “security officer” licence to buy firearms in addition to his state licence and concealed carry permit.

Prior to this incident, G4S had previously been accused of improperly vetting its employees. One incident involved a former paratrooper who killed two colleagues in Iraq, allegedly claiming to be the “antichrist.” An official investigation revealed that G4S did not properly vet his psychological health.

The Incident

On June 12, 2016, Pulse Nightclub, an LGBTQ nightclub, was hosting its popular Latin Night. Just after 2:00 AM that night, more than 300 people were inside the nightclub when Mateen opened fire near the entrance. After an off-duty police officer engaged in gunfire with Mateen, and several police officers with SWAT training exchanged gunfire with Mateen, Mateen was allegedly able to continue to move through the club. At 2:35 in the morning, Mateen allegedly called 911 and professed his “allegiance to Abu Bakr al-Baghdadi of the Islamic State.” After police had cornered Mateen in a bathroom area, the situation became a hostage situation, and Mateen spoke to negotiators three times. At 5:02 in the morning, Orlando police triggered a controlled detonation and smashed through the wall of the club with an armoured vehicle. Mateen was killed after engaging in a gun battle with about a dozen officers. At the time of the shooting, the Pulse attack was the deadliest mass shooting in United States history, with 49 fatalities.

Legal Aspects

Court cases

A lawsuit was filed by victims, survivors, and representatives alleging that G4S, the security company that provided firearms training to Mateen, should be held liable for damages resulting from the attack. The lawsuit alleged that the security firm ignored his comments supporting violence prior to the mass shooting, and failed to remove his service weapon and recommend his firearms licence be removed when they should have.

However, a judge threw out the lawsuit in April 2019, writing that G4S did not have civil liability for the attack because Mateen was not working for the firm at the time of the attack.

The International Code of Conduct

Further, the International Code of Conduct requires stringent selection and vetting of personnel, assessment of performance and duties (paragraphs 45 to 49), and training of personnel of the Code and relevant international law, including human rights and international criminal law (paragraph 55). Meeting the requirements of the Code of Conduct, can help private security companies and their clients ensure that private security personnel are qualified, trained, supported, informed, and responsible.

Meeting the requirements of the Code of Conduct can help private security companies and their clients ensure that private security personnel are qualified, trained, supported, informed, and responsible.


Settlements and Fines

G4S, who employed Mateen, was fined $151,400 by the Florida Department of Agriculture and Consumer Services for allegedly  providing inaccurate psychological testing information on forms that allowed employees to carry guns. The Department discovered that G4S had listed the name of a psychologist who no longer practised as the screener on Mateen´s form, in addition to more than 1,500 other employees over a 10 year period.

The amount was the largest on record under the specific state law.

Stock Prices

Once it was revealed that Omar Mateen, the shooter at Pulse Nightclub, was a G4S employee, shares in G4S fell dramatically. The G4S shares dropped by as much as 7.5%. When G4S´s shares dropped, it wiped out about $280 million in company value.


What role does continuous psychological evaluation play in the vetting of security personnel?

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Case prepared by Madison Zeeman


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