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Negligent Security Expert Witness

Florida | Nationwide | Investigations HQ, LLC — License #A170078

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When a crime occurs on someone's property, the question isn't only who committed the act — it's whether the property owner did enough to prevent it. Negligent security is one of the most consequential and complex areas of premises liability law, and the strength of an expert witness can make or break a case.

Mark J. Lang, MCJ, CPP, CHPA, the founder of Investigations HQ, LLC, is a nationally recognized negligent security expert witness. With more than four decades of combined experience in law enforcement, corporate security, and private investigations — and credentials at the very top of the security profession — he delivers credible, fact-based testimony that holds up under the most rigorous cross-examination.

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What Is Negligent Security?

Negligent security is a form of premises liability that arises when a property owner or manager fails to implement reasonable security measures, and that failure allows a foreseeable criminal act to harm a person on the property. The legal standard centers on foreseeability: did the owner know or should they have known that criminal activity was a realistic risk?
 

Negligent security claims commonly arise at:

  • Apartment complexes and multi-family residential properties

  • Hotels, motels, and short-term rental properties

  • Parking lots, garages, and transit facilities

  • Bars, nightclubs, and entertainment venues

  • Shopping centers and retail properties

  • Gas stations and convenience stores

  • Schools, universities, and daycare facilities

  • Hospitals, clinics, and healthcare facilities
     

Common Security Failures in Negligent Security Claims

A thorough expert review evaluates whether the property owner met the standard of care for a reasonably prudent owner. Common failures include:

  • Broken, poorly positioned, or absent CCTV cameras

  • Inadequate or non-functioning exterior lighting

  • Unsecured gates, doors, fences, or perimeter access points

  • Failure to conduct or act on a prior security risk assessment

  • Insufficient security guard presence or patrol protocols

  • Ignoring prior criminal incidents on or near the property

  • Failure to notify tenants or guests of known security risks
     

The Standard of Foreseeability

A cornerstone of any negligent security case is establishing that the harm was foreseeable. Expert witnesses are essential in demonstrating this. Mr. Lang reviews police reports, prior incident histories, 911 call records, and crime statistics for the area to build a compelling case — or to objectively evaluate whether the standard of care was met — depending on whether he is retained by the plaintiff or defense.
 

Why Choose Mark Lang as Your Negligent Security Expert?

Mark Lang's background is uniquely suited to negligent security litigation. As a former law enforcement captain and head of security for a major Florida health system, he has both the investigative credentials and the security management expertise to evaluate complex cases with authority.
 

  • Certified Protection Professional (CPP) — the gold standard in security management

  • Retired Special Investigations Division Captain, Orange County Sheriff's Office

  • Former Executive Senior Director of Security, Orlando Health

  • Master of Criminal Justice, Boston University

  • Florida Licensed Private Investigator, License #A170078

  • Active in ASIS International and the Florida Association of Licensed Investigators
     

Litigation Services Provided

  • Case record review (incident reports, security logs, CCTV footage, property records)

  • Written expert report and opinion

  • Case strategy consultations with counsel

  • Deposition testimony

  • Trial testimony
     

Serving Florida and Beyond

Based in Orlando, Investigations HQ serves attorneys handling negligent security cases throughout Florida — including Miami-Dade, Broward, Palm Beach, Hillsborough, Orange, Seminole, and Duval counties — and accepts engagements nationwide.

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