Criminal Investigation Expert Witnesses: 12

Experienced in Fire Cause and Origin, Arson Prosecution and Defense, Product Subrogation, Fire and Building Codes, Life Safety Codes, Fire Injuries and Fatalities, as well as Fire Department Operations and Management. 

John Michael Agosti & Associates provides assistance to insurance companies, attorneys and other agencies in the determination of cause and origin in fires and explosions. Our goal is to provide independent and articulate findings to you the client, quickly and accurately. 

With over 28 years of fire department experience and 15 years in the private sector, Mr. Agosti has completed over two thousand investigations of fires, explosions, and life safety incidents. He has testified in both federal and state courts for both plaintiff and defense clients.

Andreu Experts is a premier expert witness and consulting firm specializing in Law Enforcement Practices, with a distinct focus on Homicide Investigations, Use of Force, and Complex Criminal Case Analysis. Founded by a former Chief of Police with more than 45 years of distinguished law enforcement experience—including over two decades dedicated to homicide investigations—Andreu Experts delivers authoritative, fact-driven opinions grounded in real-world investigative leadership.

Their firm provides comprehensive expert services to both plaintiff and defense attorneys in state and federal courts. They are retained in cases involving wrongful death, police procedures, investigative failures, officer-involved shootings, and allegations of misconduct. Every opinion rendered is the product of meticulous case review, careful analysis of reports, witness statements, forensic evidence, and adherence to generally accepted law enforcement standards and practices.

What distinguishes Andreu Experts is not only the depth of experience, but the credibility and clarity brought to each case. Having led major investigations and supervised detectives in high-stakes environments, their principal understands how investigations should be conducted—and where they fall short. This perspective allows them to identify critical issues, explain complex procedures in plain terms, and assist attorneys in building compelling, well-supported arguments.

Services include case evaluation, report writing, deposition and trial testimony, and trial preparation support. They work closely with legal teams to strengthen case strategy, anticipate opposing arguments, and present findings in a manner that resonates with judges and juries alike. Whether retained early in litigation or brought in to assess an existing case, Andreu Experts provides objective, defensible opinions that stand up under scrutiny.

Andreu Experts' commitment is to professionalism, integrity, and precision. They do not advocate—they analyze. Their role is to assist the trier of fact in understanding what occurred, why it matters, and how it aligns with accepted law enforcement standards. When experience matters and credibility is critical, Andreu Experts is a trusted partner in the pursuit of justice.

Archuleta & Associates Investigative Services, a Division of Archuleta & Associates, Inc., has been providing investigative services within various industries since 1982. They are the overwhelming leaders within the CA Central Valley. The clientele of Archuleta & Associates, Inc. consists of every level of business, from both the private and public sector. Due to the wide range of services provided and their 25 years within the industry, they have worked with an extremely diverse and vast clientele base, from the largest of litigation firms to the smallest of personal clients. 

Robert A. Archuleta launched his career as a Private Investigator in 1983, after five years as an officer, investigator and sergeant for the Lodi Police Department, followed by stints as an engineering contractor and a deputy U.S. Marshal. Among his other clientele, Mr. Archuleta has been as an Expert Witness for the Department of Consumer Affairs for the State of California. 

Services Include:

My name is David T. Sweeney.  I am a Police Policy and Procedure expert and a retired 34-year veteran police leader with Seattle Police and Oregon State University PD.  I have decades of experience supervising a large number of police officers and supervisors. I am currently employed as adjunct faculty in the School of Police Staff and Command at Northwestern University. I enjoy assisting with expert reviews of policing best practices for a variety of legal standards for police departments. As an expert witness, I have been pleased to work with both plaintiff and defense attorneys. I will give you an honest assessment of your case, so that I can provide the best reports and helpful testimony. I have experience with 65+ total cases: 1/3 defense cases and 2/3 plaintiff cases.

Litigation Support - My goal is to improve best practices in policing by offering expert witness and police consultation services. I am also a trained mediator specializing in workplace conflicts. I provide honest, unbiased opinions. I will be happy to review and discuss your case. I will point out strengths and weaknesses of the case, and we can work on next steps, whether it be further case review, expert report, deposition, or trial testimony. I have spent 21 years as a sergeant and lieutenant, responsible for training and reviewing topics such as police pursuits, use of force, police tactics, de-escalation, police supervision, less lethal weapons, active shooter, SWAT, crowd control, legal standards, EEO, Human Resources, U.S. 1983 cases, and more.

 Areas of Expertise:

View David T. Sweeney's Consulting Profile.

Global Forensic Services, LLC (GFS) is a Forensic Consulting, Laboratory and Investigative Firm offering over 44 years of experience and training in a wide range of forensic science and private investigation disciplines.

Larry Stewart has personally examined tens of thousands of individual items of evidence from sources such as state, local, and federal agencies (e.g. Federal Bureau of Investigation, Secret Service, Bureau of Alcohol, Tobacco and Firearms, Central Intelligence Agency, and others), and foreign governments. On several occasions he has examined cases involving international disputes between governments. 

Mr. Stewart has testified as an Expert Witness in state, federal and military courts of law, as well as in foreign court systems to include; Austria, Australia, Canada, Germany, Singapore, Sri Lanka, Switzerland and Thailand. He has also testified at The Hague in the Netherlands and three times as an expert before the U.S. Congress. 

Areas of Expertise Include:

Mark J. Lang, MCJ, CPP, CHPA, is the Owner of Investigations HQ, LLC, a Florida-based law enforcement and security consulting firm. With more than 40 years of experience in Law Enforcement, Healthcare Security, and Security Management, Mr. Lang is recognized as an expert in negligent security, premises liability, hospital security, law enforcement practices, and police standards and procedures.

Mr. Lang retired from the Orange County Sheriff's Office (Florida) as a Captain assigned to the Special Investigations Division, where he supervised specialized units including Undercover Narcotics, Fugitive Apprehension, Criminal Intelligence, Vice, Pharmaceutical Investigations, and various federal and local task force operations. His extensive law enforcement career included leadership assignments in patrol, tactical operations, criminal investigations, and special operations.

Following his law enforcement career, Mr. Lang became the first Executive Senior Director of Security Operations for Orlando Health, one of the nation's largest healthcare systems. In this role, he was responsible for enterprise-wide security operations, workplace violence prevention programs, emergency management coordination, behavioral health security, and regulatory compliance. He is widely recognized for his expertise in hospital security management and healthcare workplace violence prevention.

Areas of Expertise:

Mr. Lang holds a Master of Criminal Justice degree from Boston University and a Bachelor of Arts in Criminal Justice Administration from Columbia College. He is board-certified as a Certified Protection Professional (CPP) through ASIS International and a Certified Healthcare Protection Administrator (CHPA) through the International Association for Healthcare Security and Safety (IAHSS).

Mr. Lang has consulted on more than 60 cases involving negligent security, premises liability, healthcare security, law enforcement practices, use of force, workplace violence, patient elopement, security operations, and police standards and procedures. He has provided expert analysis, case review, and report preparation throughout the United States. 

Dr. Heather L. Manning is recognized Forensic Criminologist and Subject Matter Expert specializing in violent crime, sexual exploitation, domestic violence, and human trafficking. With nearly two decades of experience spanning academia, clinical practice, child welfare, corrections, and law enforcement collaboration, Dr. Manning brings a rare interdisciplinary perspective to the analysis, investigation, and prevention of complex criminal behavior.

Dr. Manning holds a Ph.D. in Forensic Psychology and has extensive expertise in criminal profiling, behavioral analysis, forensic interviewing, and trauma-informed investigative practices. She currently serves as a Professor and Subject Matter Expert at Evidentia University, where she teaches graduate-level courses in criminal profiling, psychological profiling, and behavioral analysis grounded in FBI-aligned methodologies. Her academic work emphasizes offender typologies, victimology, and the behavioral dynamics of violent and sexually motivated crimes. She also works as a cold case investigator and a research IRB board member.

Litigation Support - Providing expert witness consultation and testimony in legal proceedings. Services include case review and expert opinion development, written expert reports, deposition preparation and testimony, trial testimony, and consultation on behavioral evidence, offender dynamics, victim behavior, and trauma impact.

Areas of Expertise

An active scholar and author, Dr. Manning’s research and publications focus on sexual violence, offender behavior, trauma, and systemic failures in protection and response. Her work includes peer-reviewed research, professional conference presentations, and authored books addressing serial violence and survivor experiences.

Dr. Manning is a member of the American Institute for the Advancement of Forensic Sciences, and the Society for Police and Criminal Psychology. She is widely respected for her ability to bridge clinical insight, academic rigor, and real-world investigative application—advancing justice, victim-centered practice, and professional excellence across forensic and behavioral disciplines.

View Heather Manning's Consulting Profile.

Joseph E. Gunja is a Jails, Prisons and Corrections Expert with more than 30 years of experience in the corrections industry. Mr. Gunja had a distinguished career with the Federal Bureau of Prisons (FBOP) for over 28 years serving as a Correctional Officer, Shift Supervisor, Investigator, Captain, Associate Warden, and Warden at three complex correctional facilities. 

Litigation Support - Joseph Gunja has an over 90% success rate in all cases he has been retained as an expert, both working with plaintiffs and defendants, as well as several cases of sentencing mitigation or reductions.  While some cases were settled in lieu of court, the settlements were all in favor of the attorneys or firms he represented. He offers advice, expertise, and expert testimony for a variety of issues in matters pertaining to: 

What Really Happens Inside a Prison

Mr. Gunja also served as Regional Director of the Western Region for over 2 years and was assigned to the FBOP's Headquarters in Washington, DC where he was responsible for authoring national policy and official publications, providing technical expertise to the Assistant Director of Correctional Programs and facility Wardens, Associate Wardens, and Captains. 

After retiring from the FBOP in 2007, Mr. Gunja has been providing correctional consultation and expert witness services. In addition, he has worked for two of the largest private corrections companies, CCA and GEO Group, as Warden at the Northeast Correctional Center in Youngstown, Ohio, and the Great Plains Correctional Facility in Hinton, Oklahoma.

View Simco Correctional Consulting's Business Consulting Profile.

Dr. Roy G. Taylor is a current Chief of Police with over 40 years of experience in a wide-range of federal, state, local, and private criminal justice positions. Dr. Taylor specializes as an expert witness in Police Practices and Procedures and Law Enforcement and Criminal Justice. Current Positions:

• Chief of Police Blue Ridge Public Safety (2014)
• President/CEO Signal 88 Security of Charlotte (2012)
• President/CEO Capitol Special Patrol (2012)
• Chief of Police Capitol Special Police (2002)
• Lt. Colonel – Provost Marshal, Army National Guard (2000)
• Antiterrorism / Emergency Management Branch Chief DoD (2007)
• Provost Marshal Joint Civil Support Task Force, Joint Chiefs of Staff (2014)

Litigation Support - Dr. Taylor is called upon to analyze cases from both defense and plaintiff perspectives. His services include case review, written reports, deposition, and trial testimony as needed. 

Areas of Expertise:

View Roy Taylor's Consulting Profile.

Beth A. Mohr, CFE, FSA, CFCS, CAMS, CCCI, MPA, PI, is a Police Practices expert with over 30 years of sworn and non-sworn investigative experience.  Ms. Mohr has testified as an expert in numerous state and federal court proceedings, depositions, and administrative hearings in federal and state courts, including New Mexico, Ohio, Illinois, Arizona, California, and Washington State.  Ms. Mohr has testified on a variety of subjects, including police procedures, police misconduct, white-collar crime, and fraud examinations.  Her expertise has been verified by the courts via a Daubert challenge, in which Ms. Mohr was found to be qualified as an expert in police practices generally, and well as the specific areas of interviewing, interrogation, false and recanted confessions, cognitive bias, investigations and investigative failures, vice, and human trafficking.  Ms. Mohr is neutral, fair, and her opinions are rooted in provable facts, as well as academic literature, where appropriate.  She strives to balance her cases between defense and plaintiff-sided cases, and also provides habeas consulting services.  

Ms. Mohr is credentialed as a Nationally Certified Law Enforcement Instructor by the IADLEST, and is one of fewer than 150 individuals who have been nationally certified as an expert law enforcement instructor.  She is a Certified Fraud Examiner, Certified Force Science Analyst (FSA) Certified Anti-Money Laundering Specialist (CAMS), Certified Financial Crimes Specialist (CFCS) and a Certified Cyber Crimes Investigator (CCCI).  She is also a Private Investigator (PI) licensed in New Mexico, Arizona, Texas, and California.  

Areas of Expertise:

• Police Practices and allegation of Police Misconduct
• Excessive Force, Deadly Force & Use-of-Force
• Taser, ECWs, and other uses of force intended to be less-lethal
• Interviewing, Interrogations & False and Recanted Confessions
• Police Ethics & Ethical Failures
• Cognitive Bias, Confirmation Bias
• Investigative Failures
• False Arrest
• Failure to Train, Failure to Supervise, Monell Claims
• Evidence Handling
• Police Policy, SOPs
• Habeas Consulting, including death penalty cases
• Sex Trafficking and Human Trafficking
• Sexual Assault
• Fraud & White-Collar Cases
• Retaliation & Qui Tam
• Workplace Violence & Sexual Harassment
• Private Investigations & PI Failures

During her career with the San Diego Police Department, Ms. Mohr was awarded three Commanding Officer’s Citations, which were the highest awards offered by the San Diego Police Department for investigative acumen at the time.  After retiring from the San Diego Police Department, she conducted death penalty mitigation investigations and other complex felony investigations, including homicide and white-collar cases, for the Whatcom County, Washington, Public Defender’s Office.  This includes conducting investigations of allegations of police misconduct for the City of Albuquerque Independent Review Office. Ms. Mohr recently chaired the City of Albuquerque’s Police Oversight Board, a civilian board that was created as part of the US Department of Justice’s Consent Decree with the City of Albuquerque and the Albuquerque Police Department.

Ms. Mohr has published a chapter entitled “Skepticism”, in the newly-released book The Art of Investigation Revisited, as well as having penned articles for bar journals and other peer-reviewed publications.  Ms. Mohr has taught courses on law enforcement topics, including interviewing techniques, investigative ethics, evidence collection, financial and fraud investigations, and many other topics. Her ethics courses, investigative courses, and fraud courses are certified for law enforcement credit.

“We settled the case...for $5 million. Your report played a huge role in that.  Thank you for everything!”  Nick H. 

Adam Bercovici has over 40 years of experience in the Police and Security field. Mr. Bercovici spent 30 of those years with the LAPD, 20 as a supervisor and manager. He is currently a retired LAPD lieutenant and former security company CEO.

Background: Mr. Bercovici's leadership assignments included the Criminal Investigation Section- Major Crimes Division-The Joint Terrorism Task Force, The FBI Violent Crime Task Force ( where he supervised the FBI Fugitive Task Force), The Special Investigation Section, and Homicide Special Section. 

Since 2012, Mr. Bercovici has worked as a subject matter expert and consultant in Police Practices and Complex Police Investigations. His clients have included major law firms, insurance companies, and corporations.  Mr. Bercovici is currently retained on several high-profile cases.  He is an experienced Expert Witness who has written numerous Rule 26 Reports and has testified in both State and Federal courts.  Writing examples can be provided.  Mr. Bercovici has been an on-air talent, producer, and script and story consultant in the entertainment industry.  He was the Co-Talent on The History Channel Series JFK Declassified-Tracking Oswald.  Mr. Bercovici was the Executive Producer for American Cartel for Discovery Plus. 

Litigation Support: Adam Bercovici splits his work between defense and plaintiff. He has been retained by prominent civil rights firms, major municipalities and their legal counsel, plaintiff attorneys, city attorneys, and criminal defense attorneys. Mr. Bercovici accepts work based on the merits of the individual case.

Areas of Expertise: 

Tony Turnbull is a retired Sergeant with the Sacramento County Sheriff's Office. He has over 30 years of Law Enforcement experience with over 20 of those years in Criminal Investigations.  Sgt. Turnbull spent over 20 years of his career in Investigations, including 6 years in Gangs and Narcotics and 16 years in the Homicide Bureau, including 3 years as the Homicide Bureau Supervisor and 5 years in Cold Case Investigations. 

Sgt. Turnbull is currently providing consulting and expert witness services, instructor with Robert Presley's Institute of Criminal Investigations, and working cold case homicide investigations as a retired annuitant at the Sacramento County Sheriff's Office.

Litigation Support - Sgt. Turnbull provides expert witness testimony and consulting services in both civil and criminal litigation, offering clear, methodical, objective opinions grounded in law enforcement standards, policy compliance, and constitutional policing. He also provides expert review of historical police investigations, applying current or past professional standards to cases. Domestic and international travel offered as needed.

Areas of Expertise: