When You Are in a Hurry and Looking for Just the Right Expert Witness to Win Your Case.

DUI Officer Drug Recognition Expert Witness

Provides Opinion & Testimony In:

DUI, DWI, Felony, Field Training Officer, Officer, California Highway Patrol, CHP, Law Enforcement, DUI Checkpoints, Protective Service Detail, Drug Recognition Expert, Accident Review,

Expert Witness No.1230


  • Former officer of the California Highway Patrol (CHP) with over eighteen years of law enforcement experience.
  • Graduated from the CHP Academy in October of 1999. After completing the academy, worked in the following areas:
  • November 1999 to January 2002 – Hollister/Gilroy January 2002 to October 2002 – Los Banos October 2002 to January 2018 – Fresno

Duties as an officer:

  • Road Patrol to include Driving Under the Influence (DUI) enforcement
  • Provided safety and service to motorists
  • Provided security to state employees
  • Assisted with DUI checkpoints
  • Served as Officer in Charge when no supervisors were available
  • Field Training Officer
  • Served on the Protective Service Detail
  • Investigated and assisted with traffic collisions
  • Investigated and assisted with DUI, felony, and complex investigations
  • Investigated crimes on state properties
  • Authored and served search warrants
  • Assisted allied agencies
  • Served as the Terrorism Liaison Officer
  • Drug Recognition Expert and Instructor for the California Highway Patrol
  • Taught officers throughout the United States and Canada in drug education
  • Taught drug education to school administrators, nurses, and teachers
  • Assisted with California Highway Patrol Explorer Program
  • Assisted with homeless enforcement on State property

In June of 2010, became certified through the National Highway Traffic Safety Administration (NHTSA) as a Drug Recognition Expert (DRE) Instructor. To maintain qualifications as as instructor attended a recertification class, which was held every two years. Have personally evaluated over 275 people who were suspected of being under the influence of drugs or a combination of drugs and alcohol. Maintained a rolling log documenting these evaluations.
Have instructed hundreds of officers in both a classroom setting and a field training setting. In the classroom setting, have facilitated and instructed several hundred officers in the sixteen hour Advanced Roadside Impairment Driving Enforcement (ARIDE) course.
Have instructed officers at the DRE School and DRE Pre-School, which included classroom lectures and assisting with multiple DUI wet labs. Have also instructed officers at the DRE recertification class.
In the field training setting, have facilitated and instructed hundreds of officers in completing a DRE starting with the arrest of an impaired subject, properly evaluating the impaired subject, and properly and thoroughly documenting the evaluation of the impaired subject. Properly instructed the officers to complete all DRE paperwork and enter their evaluations into the NHTSA tracking system.
Reviewed and critiqued hundreds of DRE evaluations, during DRE training and in the field, to maintain accuracy for the CHP and for the DRE program
In addition to teaching officers, taught employees at the Department of Transportation and at the Fifth District Court of Appeals in how to recognize drug use among employees.

  • Taught several school administrators, school counselors, school nurses, and teachers Drug Impairment Training for Educational Professional (DITEP).
  • 2016 to 2017 – In charge of coordinating the training and operations for the DRE program for the CHP, Fresno Area office.
  • 2016 to 2017 – Assisted with coordinating the training and operations for the DRE program for the CHP, Central Division.
  • June 2010 – Certified as a DRE Instructor (NHTSA and POST certified) (DRE Instructors
    T. Herbert and R. Horrocks). Part of the certification included teaching at a DRE class and supervising four DRE evaluations under the watch of a DRE instructor
  • February 1-5, 2010, Certified as a Standardized Field Sobriety Test Instructor (NHTSA and POST certified) (DRE Instructor T. Herbert). Part of the certification included teaching two SFST modules during the training.
  • August 25 – September 1, 2005 – Certified as a DRE (NHTSA and POST certified) (DRE Instructors D. Erickson and E. Skidmore). Part of the certification included the DRE evaluation of twelve subjects and either putting them under the influence of a controlled substance or ruling out impairment.
  • December 17-19, 2002 – Attended CHP Advanced Drug Training.


  • Division Chief Commendation for Exemplary Job Performance
  • Division Chief Commendation for Outstanding Performance
  • Certificate of Special Congressional Recognition from Congressman Jim Costa
  • Division Chief Commendation for Exemplary Performance
  • Letter of Commendation from Fresno City Mayor Lee Brand
  • United States Senate Certificate of Commendation from US Senator Dianne Feinstein
  • California State Senate Certificate of Recognition fromSenator Tom Berryhill
  • 2017 Exchange Club of Fresno Top Cop Award for CHP
  • Ten 10851(A)CVC Awards


  • Horizontal Gaze Nystagmus: The Science & The Law – A Resource Guide for Judges, Prosecutors and Law Enforcement (Dusty Hoffman, Missouri State Highway Patrol)
    Legal Update on Blood Draws in DUI Cases (Orange County District Attorney Office)
  • Measuring Nothing: The Unreliable Measurement of THC in Drivers is Bad News for the Justice System (Utilizing Forensic Science in Criminal Cases – Jeremy Brehmer and Michael Nichols)
  • The Science is on Your Side: What You Need to Know About Cannabis and Psychomotor Performance (Paul Armentano, Deputy Director NORML)
  • A Two Year Study of Delta 9-tetrahydrocannabinol Concentrations in Drivers: Examining Driving and Field Sobriety Test Performance (Journal of Forensic Sciences – Kari Declues M.S, Shelli Perez M.S., and Ariana Figueroa M.S.)
  • Horizontal Gaze Nystagmus: A Review of Vision Science and Application Issues (Journal of Forensic Sciences – Steven Rubenzer Ph.D. and Scott Stevenson Ph.D.)
  • Drug Identification Performance on the Basis of Observable Signs and Symptoms (Accident Analysis and Prevention – David Shinar and Edna Schechtman)
  • Residual Cannabis Levels in Blood, Urine, and Oral Fluid Following Heavy Cannabis Use (Forensic Science International – Morris Odell, Matthew Frei, Dimitri Gerostamoulos, Mark Chu, and Dan Lubman)
  • DWI Prosecutor’s Handbook (National Traffic Law Center)
  • Challenges and Defenses II – Clams and Responses to Common Challenges and Defenses in Driving while Impaired Cases (National Traffic Law Center)
  • Horizontal Gaze Nystagmus: The Science and the Law (National Traffic Law Center)
  • Marijuana, Alcohol, and Actual Driving Performance (NHTSA)
  • Cross-Examination for Prosecutors (National Traffic Law Center)
  • Drug-Impaired Driving: Understanding the Problem and Ways to Reduce It: A Report to Congress (NHTSA)
  • Drugs and Human Performance Fact Sheets (Fiona Couper and Barry Logan)
  • Admissibility of Horizontal Gaze Nystagmus – Targeting Hardcore Impaired Drivers (American Prosecutors Research Institute – John Bobo, Marcelline Burns, Karl Citek, and Stephen Talpins)
  • Establishing Legal Limits for Driving Under the Influence of Marijuana (Injury Epidemiology – Kristin Wong, Joanne Brady, and Guohua Li)
  • Marijuana-Impaired Driving – A Report to Congress (NHTSA – Richard Compton)
  • The Drug Evaluation and Classification (DEC) Program – Targeting Hardcore Impaired Drivers (American Prosecutors Research Institute)
  • Overcoming Impaired Driving Defenses – Targeting Hardcore Impaired Drivers (American Prosecutors Research Institute – John Bobo and Herbert Tanner)
  • Alcohol Toxicology for Prosecutors – Targeting Hardcore Impaired Drivers (American Prosecutors Research Institute – John Bobo, Patrick Harding, and Jane Starnes)
  • Drug and Alcohol Crash Risk (NHTSA – Richard Compton and Amy Berning)
  • The Robustness of the Horizontal Gaze Nystagmus Test (NHTSA – Marcelline Burns)

All Training Classes Attended:

  • 24 Hour CHP Advanced Drug Training
  • 80 Hour CHP Advanced Accident Investigation
  • 80 Hour Drug Recognition Expert School
  • 40 Hour CHP Auto Theft Training
  • 24 Hour CHP Advanced Officer Safety Training Course
  • 8 Hour Concealed Trap and Compartment Training Class
  • 8 Hour M.A.G.E.C. Gang Conference
  • 16 Hour Interview and Interrogation Class for Patrol Officers
  • 8 Hour Street Development Class
  • 8 Hour Emerging Drug Trends and Drugs of Abuse Class
  • 8 Hour Brand Piracy and the Links to Organized Crime and Terrorism Class
  • 8 Hour Chasing Cell Phones Class
  • 40 Hour CHP Standardized Field Sobriety Testing Instructor Course
  • 8 Hour Pharmaceutical Diversion Class
  • 8 Hour Search Warrant and Miranda Class
  • 16 Hour Canine Agitation Training Class
  • 16 Hour CHP Drug Recognition Instructor Upgrade Course
  • 8 Hour Anti-Terrorism Concepts for Patrol Personnel
  • 16 Hour Criminal Street Gang Investigations Class
  • 16 Hour Criminal Street Gangs Overview online course
  • 16 Hour Pharmaceutical Diversion Training
  • 8 Hour CHP Critical Incident Investigation Team Training
  • 2 Hour Law Enforcement Telephone Investigations Course
  • 8 Hour Violent Gang Infiltration Through the Use of Informants
  • 8 Hour National Improvised Explosive Familiarization Training
  • 8 Hour Sovereign Citizen Extremist Training
  • 8 Hour Advanced Explosive Recognition Class
  • 16 Hour Search Warrants A Through Z Class
  • 8 Hour Hidden Compartment Training
  • 8 Hour Drug Endangered Children Training
  • 16 hour Law Enforcement Active Shooter Emergency Response Training
  • 8 Hour Bath Salts Training
  • 8 Hour Terrorism Liaison Officer Basic Training
  • 8 Hour Shiite Extremists Hezbollah and Hamas Training
  • 8 Hour Cyber Security and Cyber Terrorism Training
  • 8 Hour Surveillance Techniques Training
  • 40 Hour Post Blast Investigator School
  • 40 Hour Interview and Interrogation Class
  • 80 Hour Core Investigation Class
  • 40 Hour Sexual Assault Investigator Training
  • 8 Hour Firearms Identification and E-Trace Training
  • 80 Hour Homicide Investigator Training
  • CNOA 51st Annual Training Conference
  • 8 Hour Homegrown Violent Extremism Training
  • 8 Hour Intellectual Property Crimes and the Illicit Underground Training
  • 40 Hour Crime Scene Investigation Class
  • 8 Hour Avoiding the Chemical Bullet
  • 10 Hour M.A.G.E.C. Gang Conference
  • California Peace Officers Standards and Training Learning Portal