Biology - Biological Sciences Expert Witnesses: 4

Dr. Ewen Todd is a Food Safety Expert with over 45 years of knowledge and experience in general food safety and Food Microbiology Issues. Specifically, he has extensive experience in the reporting and surveillance of Foodborne Disease, as well as development of analytical methods for identifying foodborne pathogens. As a result of his work with the industry and his knowledge of foodborne disease, Dr. Todd has influenced research programs and regulatory approaches taken by the Health Protection Branch of Health Canada. In the US, he held the position of Director of the National Food Safety and Toxicology Center and the Food Safety Policy Center at Michigan State University. 

A leader in microbial research, foodborne disease surveillance, costing of outbreaks, food safety policy, seafood toxins, standard-setting, risk assessment, risk management, and risk communication. He has worked in numerous countries educating and training, and collaborating to set up surveillance systems, food safety policies, regulations, and HACCP and other control strategies, including China, Cambodia, Japan, United Arab Emirates, Lebanon, Kuwait, Saudi Arabia, and Europe, as well as Canada and the USA. He is also familiar with food defense and food fraud issues, and waterborne disease. He is familiar with the US and Canadian food industry, both foodservice and food processing, HACCP, disease investigation, food, and equipment contamination.

Since leaving the Canadian government and entering academia and as a consultant, he has been an expert witness in 25 cases in both the U.S. and Canada where foodborne illnesses have occurred. He has testified on the behalf of plaintiffs who suffered from E. coli O157:H7, Campylobacter, Salmonella, ciguatoxin fish poisoning, yeast, and unknown agents. He has also represented defendants in two illness cases. Therefore, his litigation services are available for both Plaintiff and Defense.

Areas of Expertise

• General Food Safety and Spoilage Issues
• HACCP and GHP Systems
• Standards for Poultry
• Listeria Monocytogenes in Soft Cheeses
• Standards for Poultry
• Seafood Toxins
• Food Workers
• Investigation of Foodborne and Waterborne Illnesses
• Foodborne Disease Surveillance Systems
• Risk Assessment, Risk Management and Risk Governance
• Safety of Aquaculture Systems
• Norovirus in Elder Care and Other Facilities
• Salmonella and Shigella in Schools and Child Care Centers
• Salmonella in Tahini and Other Oil-based Foods
• Escherichia coli O157:H7 in Leafy Greens
• Staphylococcus aureus in Cheese, Clostridium botulinum in Canned or Preserved Food and Native American / Inuit Fermented Food
• Listeria monocytogenes in Deli Meats and Soft Cheeses
• Controlling Listeria monocytogenes in Ready-to-eat Foods
• Hydrophobic Grid Membrane Filter Systems

View Consulting Profile.

Kirk DeLeeuw is a highly regarded and accomplished Forensic Biology and DNA Consultant / Expert Witness both nationally and internationally. He has over 20 years of dedicated experience in Molecular Biology and Forensic Science and is well respected worldwide.

Mr. DeLeeuw's career is defined by a deep technical mastery of DNA analysis, including specialized expertise in interpreting complex multi-contributor samples using Probabilistic Genotyping Software (PGS) such as STRmix. Mr. DeLeeuw is licensed by the Texas Forensic Science Commission. He likewise has a comprehensive understanding of FBI Quality Assurance Standards (QAS) and ISO/IEC 17025 accreditation requirements. He applies the standards through meticulous auditing of case files, bench notes, and high-volume electronic data files and images.

Litigation Support - Beyond the laboratory, Mr. DeLeeuw is a seasoned Expert Witness, qualified to provide testimony in Body Fluid Identification / Serology and DNA Analysis across numerous jurisdictions. He has provided sworn affidavits and oral testimony in federal, circuit, and district courts in many states including Washington DC, and internationally in the Royal Turks and Caicos Islands. His ability to translate sophisticated molecular biology data into clear, accessible testimony ensures that scientific integrity remains paramount during both civil and criminal litigations.

Mr. DeLeeuw maintains technical proficiency through a rigorous commitment to continuing education, frequently attending the International Symposium on Human Identification and National CODIS Conferences. His hands-on experience spans a wide array of instrumentation, including Applied Biosystems Genetic Analyzers and Hamilton robotic workstations, as well as various quantification and amplification kits. This combination of technical expertise, regulatory knowledge, and proven courtroom experience allows him to provide unparalleled oversight and analysis in the field of forensic DNA.

Areas of Expertise:

Background Experience - Mr. DeLeeuw's extensive professional background includes high-level roles across private and public sectors. As a Forensic DNA Analyst at DNA Labs International, he analyzed casework from across the United States and internationally, utilizing advanced PCR/STR-based methods and various chemistries. Prior to that, he served for nearly 20 years as a Forensic Scientist for the Michigan State Police.

Ryan Larrison is a senior forensic science and public sector executive with over 25 years of experience spanning Forensic Laboratory Operations, Quality Assurance, Firearms Examination, and large-scale Program and Systems Management within the Michigan Department of State Police.

Mr. Larrison currently serves in a senior leadership role within the Information Technology Division, where he directs a multi-million-dollar portfolio of enterprise systems, operations, and project delivery. In this capacity, he oversees complex, multi-agency initiatives, aligning technical execution with operational and investigative outcomes across multiple state departments. His work includes executive sponsorship of statewide technology programs and the coordination of vendors, stakeholders, and cross-functional leadership teams in high-risk, high-visibility implementations.

Litigation Support - Mr. Larrison serves as an expert witness in cases involving laboratory analysis or laboratory quality assurance. He has been deposed and/or testified over 200 times in the past 5 years.

Areas of Laboratory Expertise:

Background Experience - Prior to his current role, Mr. Larrison served as Assistant Division Director and Quality Assurance Manager for the Michigan State Police Forensic Science Division. In that role, he was responsible for the strategic direction, implementation, and oversight of quality systems across seven accredited forensic laboratories. He led all quality assurance activities, including training, corrective action programs, risk assessment frameworks, and accreditation compliance under ISO 17025 standards. His leadership resulted in a substantial reduction in non-conformities and sustained accreditation across all laboratory operations. 

Mr. Larrison has extensive experience as a program executive and project sponsor for complex forensic and evidential systems. He directed the statewide implementation of the Evidential Breath Alcohol Testing Program, including instrument selection, software integration, vendor coordination, and regulatory compliance, supported by a $2.5 million procurement process. He also led the development and implementation of a Forensic Genetic Genealogy program, establishing quality expectations, vendor deliverables, and investigative reporting standards.

George Schiro is a DNA Technical Leader - Forensic Scientist. His duties include incorporating the DNA Advisory Board (DAB) standards, accountability for the technical operations of the lab, conducting DNA analysis using the 13 STR core loci and Y STR in casework, DNA research, forensic science training and crime scene investigation.

Mr. Schiro has worked over 3500 cases and has qualified as an expert over 175 times in 31 Louisiana parish courts, Arkansas, California, Florida, Mississippi, Missouri, Nevada, New York, Texas, West Virginia, federal court, U.S. court-martial, and two Louisiana city courts. Has also consulted on cases in 29 states.

Qualified as an Expert in the Following Areas: