Automobile Collisions
Brian G. Pfeifer, Ph.D., P.E.
President and CEO
Tallahassee, FL27 years+ yrs★ 9.7
Tractor-Trailer CollisionsGuardrails / Bridge RailsConstruction Zones+11
Expert Witness Directory
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Showing 1–18 of 1,756 experts
Security and Safety
AB
A. Benjamin Mannes
Global Leader in Safety, Security, Investigations, and Emergency Management
Philadelphia, PA25 years+ yrs★ 9.7
A. Benjamin Mannes, MA, CPP, CESP is a safety and security expert specializing in public safety, security investigations, and emergency management. With a career spanning federal law enforcement, corporate compliance, and risk management, he brings a strategic and regulatory framework to his litigation work. His work centers on investigating duty-of-care obligations, assessing compliance with safety regulations, and evaluating security protocols in various sectors. Mr. Mannes has been retained in numerous expert witness and consulting engagements across the United States, involving cases related to duty-of-care liability, corporate compliance, and security management in industries such as banking, transportation, and education. His Master of Arts in Organizational Leadership, along with certifications such as Certified Protection Professional (CPP) and Certified Exam Security Professional (CESP), reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of responsibility in disputes involving security and safety compliance.
Public SafetySecurityInvestigations+1
Negligent Security
WS
William S. Marcisz
President & Chief Consultant
Apopka, FL40+ years+ yrs★ 9.7
William S. Marcisz, JD, CPP, CHPA is a security management and consulting expert specializing in negligent security and violent crime litigation. With a career spanning security administration, legal practice, and healthcare security, he brings a multifaceted perspective to his litigation work. His work centers on investigating security breaches, assessing compliance with industry standards, and evaluating whether security protocols were adequately implemented. Mr. Marcisz has been retained in numerous expert witness and consulting engagements across the United States, involving cases in healthcare, hospitality, and corporate security sectors. His Juris Doctorate in Law, along with certifications as a Certified Protection Professional (CPP) and Certified Healthcare Protection Associate (CHPA), reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of responsibility in disputes involving security management and premises liability.
Violent CrimeSecurity (Excessive) Use of ForceHospital Security+14
Emergency Medical Toxicology
DO
Daniel Overbeek, MD
Faculty, Emergency Care Specialists
Grand Rapids, MI13 years+ yrs★ 9.6
Daniel Overbeek, MD is an Emergency Medical Toxicology expert specializing in toxicology, addiction medicine, and emergency care. With a career spanning clinical practice, medical education, and toxicology research, he brings a multifaceted perspective to litigation work. His work centers on investigating toxicological impacts, assessing addiction-related medical issues, and evaluating whether emergency care standards were met. Dr. Overbeek has been retained in numerous expert witness and consulting engagements across the United States, involving cases related to toxicology, addiction medicine, and emergency medical care. His Doctor of Medicine from Wayne State University School of Medicine, along with board certifications from the American Board of Emergency Medicine, American Board of Emergency Medicine in Medical Toxicology, and American Board of Preventative Medicine in Addiction Medicine, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving medical toxicology and emergency medicine.
ToxicologyMedical Toxicology and Emergency MedicineMedical Education and Educational Theory
Forensic Psychiatry
SA
Sanjay Adhia, M.D., MRO
Forensic Psychiatrist
Sugar Land, TX14 years+ yrs★ 9.6
Sanjay Adhia, M.D., MRO is a forensic psychiatry expert specializing in forensic evaluations and brain injury medicine. With a career encompassing forensic psychiatry, brain injury medicine, and medical review, he brings a multidisciplinary perspective to his litigation work. His work centers on investigating psychiatric conditions, assessing competency and responsibility, and evaluating the impact of brain injuries. Dr. Adhia has been retained in numerous expert witness and consulting engagements nationwide, involving cases such as brain injury, competency evaluations, and psychiatric malpractice. His Doctor of Medicine from M.S. Ramaiah Medical College, along with certifications in Psychiatry, Forensic Psychiatry, and Brain Injury Medicine, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving forensic psychiatry and brain injuries.
Brain Injury Medicine
Industrial Hygiene
NM
Nancy M. McClellan
Industrial Hygiene & Safety Consultant, & Expert Witness
Shelby Twp., Michigan25+ years+ yrs★ 9.5
Nancy M. McClellan, M.P.H., CIH, CHMM is an industrial hygiene and safety expert specializing in workplace chemical, biological, and physical health and safety hazards in high hazard industries. With a career encompassing international program management, advisory board leadership, and technical authorship, she brings a strategic and globally informed perspective to her litigation work. Her work centers on investigating bioaerosol and pandemic particulate controls, assessing chemical and non-chemical disinfectant exposure risks, and evaluating facility pandemic resilience. Ms. McClellan has been retained in numerous expert witness and consulting engagements across the United States, involving cases in industries such as pharmaceuticals, construction, and healthcare. Her Master of Public Health in Industrial Hygiene, along with certifications from the American Board of Industrial Hygiene and the Institute of Hazardous Materials Management, reinforce her ability to deliver objective, defensible analyses. She is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving occupational hygiene and safety program compliance.
Indoor Air QualityOccupational hygiene and safety program training and strategic developmentCovid-19 Response Management+9
Oncology
FH
Frederick Herman Hausheer, M.D., F.A.C.P.
Physician-Scientist
Austin, TX38 years+ yrs★ 9.5
Frederick Herman Hausheer, M.D., F.A.C.P. is an oncology and pharmaceutical research expert specializing in the development and regulation of novel cancer therapeutics. With a career spanning executive leadership in global pharmaceutical research and development, he brings a strategic perspective to litigation involving drug development and compliance. His work centers on investigating patent validity, assessing regulatory compliance, and evaluating whether industry standards in oncology drug development have been met. Dr. Hausheer has been retained in numerous expert witness and consulting engagements across the United States, involving pharmaceutical research, oncology drug development, and regulatory compliance. His M.D. from the University of Missouri-Columbia, along with certifications such as Designated Clinical Investigator by the National Cancer Institute, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving pharmaceutical regulation and oncology therapeutics.
Pharmaceutical RegulationPharmaceutical ResearchClinical Development+2
Orthopedic Surgery
AL
Airell L Nygaard M.D.
Orthopedic Surgeon
Excelsior, MN42 years+ yrs★ 9.5
Airell L Nygaard M.D., FAAOS, FAAHKS is an orthopedic surgery expert specializing in forensic medicine and personal injury litigation. With a career spanning orthopedic surgery, sports medicine, and joint replacement, he brings a comprehensive framework to his litigation work. His work centers on investigating personal injuries, assessing orthopedic surgical outcomes, and evaluating whether standard of care deviations occurred. Dr. Nygaard has been retained in numerous expert witness and consulting engagements across the United States, involving cases such as slip and falls, transportation-related accidents, and sports injuries. His Doctor of Medicine from Baylor College of Medicine, along with certifications as a Diplomat of the American Board of Orthopedic Surgery and Fellow of the American Academy of Orthopedic Surgeons, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving orthopedic injuries and treatments.
Forensic MedicineFractures and soft tissue injuries of the upper extremity and handFractures, soft tissue injuries, amputations of the lower extremity and foot+3
Chiropractic
SB
Steven B. Ross
Chiropractic Physician, Expert Witness, Independent Medical Examiner
San Diego, California40+ years+ yrs★ 9.5
Dr. Steven B. Ross, DC, FASBE, DAAPM is a chiropractic and biomechanics expert specializing in motor vehicle trauma and spinal biomechanics. With a career spanning clinical practice, forensic analysis, and biomechanical engineering, he brings a multifaceted perspective to litigation work. His work centers on investigating spinal biomechanics, assessing mechanical plausibility, and evaluating whether injuries align with claimed causation. Dr. Ross has been retained in numerous expert witness and consulting engagements across the United States, involving motor vehicle accidents, spinal injuries, and soft-tissue trauma. His Doctor of Chiropractic from Northwestern Health Sciences University, along with certifications in Auto Crash Reconstruction and Whiplash and Mild Traumatic Brain Injuries, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving spinal and soft-tissue injuries.
BiomechanicsSpinal BiomechanicsMotor Vehicle Trauma+4
Real Estate
JP
Jeffery Potter
Expert Witness Real Estate, Construction and Finance
Newport Beach, CA42 years+ yrs★ 9.5
Jeffery Potter, MRED, CCIM is a real estate and construction expert specializing in complex legal disputes involving real estate development, construction processes, and financial structuring. With a career spanning over four decades in real estate, construction, and finance, he brings a multifaceted perspective to litigation work. His work centers on investigating construction defects, assessing financial structuring in real estate transactions, and evaluating whether industry standards have been met. Mr. Potter has been retained in numerous expert witness and consulting engagements across the Western United States, involving commercial real estate, construction, and financial disputes. His Master of Real Estate Development from the University of Southern California, along with his Certified Commercial Investment Member designation, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of responsibility in disputes involving real estate development and construction processes.
ConstructionReal Estate DevelopmentConstruction Processes+1
K9 operations and best practices
AB
Adam Bercovici
Results-Centric, Solutions-Focused Police Practices and Security Expert
Bend, OR40 years+ yrs★ 9.4
Adam Bercovici is a Police Practices and Security Expert specializing in police use of force and security policy litigation. With a career spanning law enforcement, security leadership, and complex investigations, he brings a strategic and operational framework to his litigation work. His work centers on investigating police procedures, assessing security protocols, and evaluating whether industry standards were met in high-risk environments. Mr. Bercovici has been retained in numerous expert witness and consulting engagements across the United States, involving police use of force, security operations, and wrongful death cases. His Bachelor of Arts in English Literature, along with California POST certifications in Basic, Intermediate, Advanced, Supervisor, and Management, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving police practices and security operations.
Use of Deadly ForceMajor Scene ManagementCrowd Management+16
Slip, Trip & Fall
JB
John Bryant
Forensic Meteorologist | Environmental Compliance Expert | AI Meteorological Specialist
Memphis, TN27 years+ yrs★ 9.4
John Bryant, AMS, NWA, EPA-Certified is a forensic meteorologist expert specializing in forensic weather analysis and environmental compliance. With a career spanning forensic weather analysis, environmental compliance, and AI-driven meteorological modeling, he brings a multidisciplinary perspective to litigation work. His work centers on investigating weather-related causation in personal injury claims, assessing compliance with environmental regulations, and evaluating the impact of weather events on legal outcomes. Mr. Bryant has been retained in numerous expert witness and consulting engagements across the United States, involving personal injury claims, insurance litigation, and wrongful death cases. His B.S. in Geosciences with an emphasis in Meteorology and Atmospheric Science, along with certifications from the American Meteorological Society (AMS), National Weather Association (NWA), and the Environmental Protection Agency (EPA), reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving severe weather events and environmental compliance.
Solar EnergyWeather & MeteorologyWrongful Death+8
Drones
HG
Harry G. Direen Jr, Ph.D, PE
Consultant, Expert Witness, COO
Colorado Springs, COOver 40 years+ yrs★ 9.4
Harry G. Direen Jr, Ph.D, PE is an Electrical and Software Engineering expert specializing in intellectual property litigation and patent infringement analysis. With a career spanning control systems, high-performance computing, and brain control interface systems, he brings a multidisciplinary perspective to his litigation work. His work centers on investigating patent validity, assessing product reverse engineering, and evaluating whether intellectual property rights have been infringed. Dr. Direen has been retained in numerous expert witness and consulting engagements across the United States, involving cases related to factory automation systems, encryption methods, and UAV control systems. His Ph.D. in Electronics Engineering / Control Systems, along with his Professional Engineer certification, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of patent infringement and validity in disputes involving complex engineering systems.
Electrical EngineeringElectronicsIntellectual Property+16
Forensic Psychiatry
MI
Mark I. Levy, MD, FAPA
Psychiatrist and Psychoanalyst
Mill Valley, CA48 years+ yrs★ 9.4
Mark I. Levy, MD, FAPA is a forensic psychiatry expert specializing in psychological trauma and mass tort/multi-plaintiff litigation. With a career spanning general psychiatry, psychoanalysis, and forensic evaluations, he brings a nuanced understanding of psychological impacts in legal contexts. His work centers on investigating psychological injuries, assessing the effects of trauma, and evaluating whether psychiatric standards of care were met. Dr. Levy has been retained in numerous expert witness and consulting engagements across the United States, involving cases such as psychological trauma from accidents, workplace stress, and PTSD. His M.D. from the College of Physicians and Surgeons, Columbia University, along with his Diplomate certifications from the American Board of Psychiatry and Neurology, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving psychological trauma and psychiatric care.
Psychological Trauma (PTSD)Mass Tort/Multi-Plaintiff LitigationGeneral Psychiatry+1
Biochemistry
CM
Christopher Matthew Byrd, Ph.D.
Senior Scientist and Executive
Bethesda, MD★ 9.4
Christopher Matthew Byrd, Ph.D. is a forensic biotechnology expert specializing in DNA forensic analysis and biochemistry in legal contexts. With a career spanning biotechnology research, program management, and strategic analysis, he brings a multidisciplinary perspective to his litigation work. His work centers on investigating DNA evidence, assessing biochemical processes, and evaluating whether laboratory standards were met. Mr. Byrd has been retained in numerous expert witness and consulting engagements across the United States, involving criminal and family law cases. His Ph.D. in Bioengineering, along with certifications as a Level III Program and R&D Manager and ANSI/ANAB laboratory assessor, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving forensic biotechnology and laboratory practices.
BiologyBiomedicalBiotechnology+15
Fire Protection Engineering
BD
Benjamin Darby Casey
Principal
New Orleans, LA23 years+ yrs★ 9.4
Benjamin Darby Casey, PE, CPP, PSP, DBIA, MBA is a fire protection and security engineering expert specializing in fire protection systems design and security integration. With a career spanning fire protection engineering, security systems, and building code analysis, he brings a comprehensive understanding of risk management and safety compliance to litigation work. His work centers on investigating fire origins and causes, assessing security vulnerabilities, and evaluating compliance with fire safety codes. Mr. Casey has been retained in numerous expert witness and consulting engagements across the United States, involving complex risk-based engineered systems and unique solutions for industries such as data centers, hospitals, and cultural institutions. His BS in Fire Protection Engineering from the University of Maryland, along with certifications such as Physical Security Professional (PSP) and Certified Protection Professional (CPP), reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving fire protection and security systems.
SecurityBuilding CodeArson+21
Banking
JH
Jay Hibert
Active Lender
Carlsbad, CA39 years+ yrs★ 9.4
Jay Hibert, Licensed California Real Estate Broker, is a banking and real estate finance expert specializing in commercial and real estate lending disputes. With a career spanning corporate banking, real estate brokerage, and financial consulting, he brings a multifaceted perspective to litigation work. His work centers on investigating lending practices, assessing real estate valuations, and evaluating whether fiduciary responsibilities were upheld. Mr. Hibert has been retained in numerous expert witness and consulting engagements across 25 states, involving commercial and real estate loans, house flipping, construction finance, and brokerage issues. His B.A. in Philosophy, Economics, and Accounting from Pomona College, along with his California Real Estate Broker license, reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of responsibility in disputes involving loan underwriting and credit administration.
Commercial Real EstateConstruction LendingEscrow/Title Insurance+8
Chronic pain
SE
Stephen E. Francis, Ph.D. ABN, FACPN
Board-Certified Clinical Neuropsychologist
Oakland, CA40 years+ yrs★ 9.4
Stephen E. Francis, Ph.D. ABN, FACPN is a Clinical Neuropsychology expert specializing in personal injury and workers' compensation cases. With a career encompassing chronic pain, anxiety, stress-related disorders, PTSD, and traumatic brain injuries, he brings a nuanced understanding of neuropsychological impacts to litigation work. His work centers on investigating symptom validity, assessing neuropsychological functioning, and evaluating the presence of malingering in complex cases. Mr. Francis has been retained in extensive expert witness and consulting engagements across California and Nevada, involving personal injury, workers' compensation, and forensic neuropsychology cases. His Doctor of Philosophy in Clinical Psychology, along with his Board-Certified Clinical Neuropsychologist designation by the American Board of Professional Neuropsychology (ABN), reinforce his ability to deliver objective, defensible analyses. He is regularly engaged by both plaintiff and defense counsel to provide clear, independent determinations of causation in disputes involving traumatic brain injuries and psychological disorders.
AnxietyStress-related disordersPTSD+3
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