Interrogation and Interviewing Expert Witnesses: 5

Dr. John R. Black is a recognized expert with extensive experience in international, federal, and state courts on Lethal Force, Police Use of Force, Officer-Involved Shootings, and Civilian Self-Defense, blending forensic analysis with human-centered perspectives and systems thinking. Dr. Black employs a systems thinking approach that enables him to view incidents from multiple perspectives. He regularly speaks to Police leadership, investigators, lawyers, and organizations about how we think about the process of inquiry, our biases, and our sensemaking.

Litigation Support - Dr. Black is qualified as an expert witness in state and federal courts related to police practices, police use of force, decision-making, officer-involved shootings, police tactics, police training, incident command, and police / jail operations. He is also qualified with similar expertise for civilian self-defense and use of force events.

Expert in Use of Force & Lethal Force Incidents & Decision-Making

In cases involving force--lethal force, understanding decision-making is as critical as the facts themselves. Whether you are a defense attorney explaining your client’s actions or a prosecutor challenging them, you need an expert who integrates both events and decision-making processes. Dr. Black offers a unique approach, blending quantitative precision with qualitative insight into how individuals make sense of their world. he is a recognized expert with experience in international, federal, and state courts on lethal force, police use of force, officer-involved shootings, and civilian self-defense. He combines forensic analysis with human-centered perspectives, ensuring a balanced view that benefits both defense and prosecution.

Advanced Forensic Video and Qualitative Analysis

Video evidence often plays a pivotal role in determining the facts. Dr. Black is skilled in forensic video analysis, using Amped Five software to extract key details. What sets him apart is his ability to combine video analysis with qualitative thematic tools like Atlas.TI, understanding both what happened and how individuals interpreted their environment under stress.

Cognitive Interviewing and Human Performance Expertise

Dr. Black specializes in cognitive interviewing, exploring clients’ mindsets during critical moments leading up to the use of force. His approach bridges the quantitative analysis of human performance with qualitative insights into violent encounters, offering a comprehensive view of why actions were taken.

Military and Law Enforcement Expertise

With 30+ years in U.S. Army Special Forces and 23+ years in law enforcement, Dr. Black brings unmatched experience to each case. He provides practical insights grounded in real-world experience. His background ensures a comprehensive understanding of how policy, training, and decision-making intersect under pressure.

View Aragon National, Inc.'s Consulting Profile.

Roger W. Chappell, has over 25 years of experience in the Law Enforcement and Security industry. His experience allows him to assist attorneys for both Plaintiff and Defense in determining whether or not minimum industry standards were met regarding premises liability. Additionally, he has a vast array of experience in criminal investigations.

Mr. Chappell has been summoned to testify as an Expert Witness in Texas District Courts on more than 20 occasions involving the following matters:

• Premises Security Adequacy
• Murder
• Capital Murder
• Felony Murder of a Police Officer
• Aggravated Robbery

Experience - Mr. Chappell is a 9 year Marine Corps Veteran and 22 year retired police supervisor in Houston, Texas. He is also a former corporate security manager, police crime prevention specialist, detective supervisor, police training manager, and internal affairs sergeant. Mr. Chappell coordinated numerous security related functions at hotels, bars and night clubs, and apartments. He has handled large events during the Super Bowl, MLB All Stars, and NCAA Final Four events. He was also a hostage negotiator for over 12 years responsible for the safe resolution to highly stressful and violent events.

Education / Training: Roger Chappell has a masters degree in Criminal Justice Management from Sam Houston State University. He has over 3,000 hours of training relating to active shooter, homicide investigations, kidnappings, interviewing and interrogation, crime scene process, and mental health issues.

Areas of Expertise:

Security Guards Negligence Bar & Nightclub Bouncers Issues Use of Force Investigations and Surveillance Detention and Arrest by Security / Non-Security Personnel

Premises Security Issues / Adequacy Security Management Police Policies and Procedures Workplace Violence Issues Unlicensed Security Activity State and Local Regulatory Compliance

View Roger Chappell's Consulting Profile.

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 41 total cases: 16 defense cases and 25 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:

Police Policy and Procedure Police Pursuits / Collisions Use of Force Less Lethal Weapons Emergency Vehicle Operator's Course (EVOC) Early Intervention Legal Standards for Police De-escalation

Crisis Intervention Equal Employment Opportunity (EEO) Special Weapons and Tactics (SWAT) Police Training Active Shooter Rapid Intervention Internal Investigations Mediation

View David T. Sweeney's Consulting Profile.

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

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
• Investigative Failure, Cognitive Bias, Confirmation Bias
• Habeas Consulting, including death penalty cases
• False Arrest
• Failure to Train / Failure to Supervise               
• Evidence Handling
• Police Policy, SOPs
• Fraud & White-Collar Crime
• Vice & Human Trafficking
• Money-Laundering Cases
• Cryptocurrencies / Bitcoin
• 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.

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: 

Police Use of Force Security Guard Operations Police Pursuit Policy Crowd Control Wrongful Death Public Safety Employment Private Investigator Best Practices

Active Shooter / Response and Training Kidnapping Special Undercover Tactics Complex Police Investigations Homicide Investigations K9 Operations Premises Liability Brady Issues