Expert Witness & Litigation Consultant
Rudolph Johnson, PhD — Toxicology Expert Witness
Rudolph Johnson
PhD • MS • BS
Two decades of federal scientific leadership at the CDC and U.S. Department of Veterans Affairs — providing courts with authoritative, peer-reviewed expertise in chemical exposure, toxic torts, and laboratory science.
Key Documents
Areas of Expertise
Litigation-ready expertise across six critical domains
Dr. Johnson's opinions are rooted in hands-on federal leadership — not theory. Each area reflects direct, documented experience at the highest levels of U.S. public health science.
Toxic Chemical Exposure
Led the nation's premier federal laboratory program for detecting human exposure to chemical agents and toxins. Expert in biomonitoring methodology, exposure attribution, and dose-response analysis.
Environmental Toxicology
National-scale evaluation of community exposure to environmental chemical hazards. Expert analysis of PFAS, heavy metals, VOCs, pesticides, and industrial contaminants in human biospecimens, water, and soil.
Forensic Toxicology & Lab Standards
Associate editor of the Journal of Analytical Toxicology. Authority on laboratory accreditation, CLIA compliance, chain of custody, and analytical validity challenges.
Military & Occupational Exposures
Directed the VA's Military Exposures Research Program, leading expert consortia across 102 VA medical centers. Deep expertise in burn pit exposures, contaminated water, and PACT Act matters.
Mass Spectrometry & Analytical Methods
Doctoral training under world-renowned mass spectrometrist Dr. Graham Cooks at Purdue. Decades of applied expertise in MS-based detection, real-time analysis, and validation of analytical methods.
Clinical Toxicology & Pharmaceuticals
MS in Pharmaceutical Sciences with a concentration in clinical toxicology (University of Florida). Expert in drug metabolism, pharmaceutical toxicity, clinical biomarkers, and pharmacokinetics.
Qualifications
Credentials, memberships & appointments
Current & Recent Positions
Director, Wisconsin State Laboratory of Hygiene
UW School of Medicine & Public Health — 2025–Present
Director, Military Exposures Research Program
U.S. Department of Veterans Affairs — 2023–2025
Chief, Emergency Response Branch
CDC, Division of Laboratory Sciences — 2013–2023
Faculty — Dept. of Pathology & Laboratory Medicine
University of Wisconsin–Madison
Advisory Board Member
Tulane University School of Professional Advancement
Professional Memberships & Editorial
Associate Editor
Journal of Analytical Toxicology
Society of Toxicology
Active Member
Society of Forensic Toxicology
Active Member
90+ Peer-Reviewed Publications
Analytical chemistry, public health toxicology, emergency laboratory preparedness
Chemical Weapons Convention — OPCW
Biomedical laboratory testing contributor, The Hague, Netherlands
Education
PhD, Analytical Chemistry
Purdue University. Studied under Dr. Graham Cooks; dissertation on real-time mass spectrometry-based detection.
MS, Pharmaceutical Sciences
University of Florida, College of Pharmacy. Concentration in Clinical Toxicology.
BS, Laboratory Robotics
Virginia Military Institute
Supporting Background
Career history establishing expert authority
Dr. Johnson's testimony is grounded in direct federal leadership experience — not academic study alone. The following career history documents the factual basis for his expert qualifications.
| Period | Role & Organization | Relevance | Key Responsibilities |
|---|---|---|---|
| 2025 – Present | Director, Wisconsin State Laboratory of Hygiene UW School of Medicine & Public Health | Lab Standards · Forensic Tox · Env. Testing | Leads Wisconsin's public laboratory across clinical, environmental, forensic, and occupational health. Oversees newborn screening, PFAS testing, forensic toxicology, metals analysis, and statewide emergency preparedness. |
| 2023 – 2025 | Director, Military Exposures Research Program (MERP) U.S. Department of Veterans Affairs | Military Exposure · PACT Act · Toxic Torts | Directed national program assessing health impacts of chemical, physical, and environmental hazards on veterans. Oversaw Toxic Exposure Fund; led expert research consortia at 102 VA medical centers. |
| 2013 – 2023 | Chief, Emergency Response Branch CDC, Division of Laboratory Sciences — NCEH | Chemical Exposure · Lab Methods · CWC/OPCW | Led development of diagnostic methods measuring human exposure to chemical agents and toxins. Directed LRN-C (45-state network). Oversaw CDC's Rapid Toxic Screen and CLIA auditing. Directed biomedical lab support for the Chemical Weapons Convention in The Hague. |
| 2003 – 2013 | Section Chief, Chemical Terrorism Methods Development Group Centers for Disease Control and Prevention | Method Validity · Detection Standards · Chem Agents | Built the nation's chemical terrorism laboratory detection capacity. Developed and validated analytical methods for chemical agent detection in human biospecimens. Set national proficiency testing standards adopted across all 50 states. |
| Pre-2003 | Research Scientist BASF Corporation | Industrial Chem. · Pharma Products | Multidisciplinary research involving small molecule synthesis and product development. Work focused on dispersions, coatings, and pharmaceutical products. |
Education
Academic foundation
Doctor of Philosophy
Analytical Chemistry
Purdue University
Studied under Dr. R. Graham Cooks, a world-recognized pioneer in mass spectrometry. Dissertation focused on real-time chemical detection — the foundational technology behind modern chemical agent identification.
Master of Science
Pharmaceutical Sciences — Clinical Toxicology
University of Florida, College of Pharmacy
Concentration in clinical toxicology. Provides direct expertise in drug metabolism, pharmacokinetics, clinical biomarkers, and pharmaceutical toxicity relevant to exposure litigation.
Bachelor of Science — Chemistry
Focus in Laboratory Robotics
Virginia Military Institute
Undergraduate training in laboratory science and instrumentation automation, providing a rigorous technical foundation for advanced graduate study in analytical chemistry.
20+
Years Federal Public Health Service
90+
Peer-Reviewed Publications
45
State Labs in National Network Led
102
VA Medical Centers Supported
3
Graduate Degrees Across 3 Disciplines
Working with Dr. Johnson
Expert witness engagement process
Dr. Johnson accepts engagements from plaintiff and defense counsel. All opinions are independent, scientifically defensible, and grounded solely in the evidence and applicable science.
Conflict Review & Case Assessment
Review of case materials to assess whether the matter falls within Dr. Johnson's areas of expertise and whether a conflict of interest exists. Initial engagement is confidential.
Scientific Record & Data Review
Thorough review of laboratory records, analytical data, exposure measurements, chain-of-custody documentation, biomonitoring data, and technical reports relevant to the matter.
Expert Report — Daubert Standard
Preparation of a rigorous, peer-grounded expert report meeting Daubert reliability and methodology standards applicable in federal and state courts.
Deposition & Trial Testimony
Clear, credible testimony drawn from first-hand federal experience. Dr. Johnson translates complex toxicological and analytical science into accessible, compelling court-ready communication.
Opposing Expert Rebuttal
Detailed scientific review of opposing expert reports, identification of methodological weaknesses, and preparation of rebuttal opinions for deposition and trial.
Litigation Strategy Consulting
Ongoing scientific consultation throughout the litigation lifecycle — including discovery support, technical deposition question development, and expert witness preparation assistance.
Contact
Retain Dr. Johnson
Dr. Johnson is available for expert witness engagements, litigation consulting, and preliminary case assessments. All inquiries are confidential and subject to conflict-of-interest review.
Responses to initial inquiries are typically provided within two business days. Please provide a brief case description, jurisdiction, and anticipated role (plaintiff/defense) when reaching out.