What is a Forensic Toxicology Expert Witness in a Criminal Case?

April 7, 2022 Criminal Defense

Expert witnesses are key players in a criminal trial who use their specific skills, expertise, knowledge, education, or training to offer an opinion that is relevant to a specific issue in a case. The purpose of rendering this opinion is to aid the trier of fact, either the judge or the jury, in coming to an overall decision regarding the issue at hand. This kind of expert differs from a typical lay witness or character witness – to read more about these differences, visit our blog here. One particular kind of expert witness that is frequently utilized in criminal cases is a toxicology expert. But what is toxicology? What do toxicology experts do and in what kinds of cases would they be used? This blog will dive into these questions and more!

Science Behind Toxicology

Generally, toxicology is the field of science that “helps us understand the harmful effects that chemicals, substances, or situations, can have on people, animals, and the environment.” Toxicologists are therefore scientists who are trained to investigate, interpret, and communicate the nature of those harmful effects.

What Does a Toxicologist Do?

Given their wide range of expertise, toxicologists are frequently called in both civil and criminal cases. Because toxicology is an interdisciplinary science, expert forensic toxicologists will integrate information from biology, and its subspecialties like genetics, endocrinology, or molecular biology, as well as physics, math, chemistry, and its subspecialties including organic, analytical, and clinical chemistry. These experts will often do scientific tests on bodily fluids or tissue samples to identify any chemicals or drugs present in the body or perform tests on the samples collected by crime scene investigators or by forensic pathologists during an autopsy. Furthermore, forensic toxicologists use:

Highly sophisticated instruments, chemical reagents, and precise methodologies to determine the presence or absence of specific substances in the sample. As part of a team investigating a crime, a forensic toxicologist will isolate and identify any substances in the body that may have contributed to the crime, such as alcohol, illegal or prescription drugs, other drugs, poisons, metals [or] gases, such as carbon monoxide.

It’s important to note that an expert toxicologist is likely not an expert in all areas of toxicology. Expert toxicologists frequently specialize in one type of issue, such as those who work in a clinical setting or forensic lab, and solely specialize in what caused a toxic reaction in a person. This kind of expert differs significantly from an expert toxicologist who specializes in workplace exposure, venomous animals or plants, or safety when it comes to companies using drugs or chemicals.

Where Do They Work?

Most forensic toxicologists work for law enforcement agencies in labs, in private drug testing facilities, or for medical examiners. Those in the justice system will call upon a forensic toxicologist to make reliable and accurate conclusions based on the pertinent science and their personal experience about the “impact a specific amount of a specific substance would have on a specific individual.” A forensic toxicology expert will then offer that opinion to the jury and explain the complex methodologies and sciences they used to come to that conclusion so trier of fact can easily understand and reach a decision. To read about an interesting case involving a criminal investigation of Broward County Medical Examiner’s Office chief toxicologist, visit our blog here.

Kinds of Investigations

A toxicology expert may be called to assist in the following kinds of investigations:

  • Analysis of blood alcohol concentration (BAC) and breathalyzer tests
  • Analysis of blood and urine alcohol tests
  • Alcohol-related incidents
  • Analysis of drug screening and confirmatory analytical results
  • Drug-related incidents including drugs of abuse, marijuana and cannabinoids, and synthetic cannabinoids
  • Adverse reactions to prescription or over the counter drugs
  • Drug safety
  • Drug standard of care

Educational Requirements

 A forensic toxicologist expert generally has a bachelor’s degree in a scientific discipline, including but not limited to chemistry, clinical chemistry, or pharmacology. Some attend forensic science programs. They may also purpose an advanced degree or certificate, such as a master’s degree in forensic toxicology, a forensic investigation certificate, or a doctorate in toxicology. Although forensic toxicologists do not need to be certified to practice, certification can heighten one’s status as an expert. The American Board of Forensic Toxicologists (ABFT) offers four certifications, including Diplomate of Forensic Toxicology (D-ABFT-FT), Diplomate of Forensic Alcohol Toxicology (D-ABFT-FA), Diplomate of Forensic Drug Toxicology (D-ABFT-FD), and Fellow of Forensic Toxicology (F-ABFT). In order to pursue the diplomate certifications, applicants are required to have a bachelor’s degree in natural science and a minimum of three years of subsequent work experience.

Other Experts That May Save Your Case

Whether testifying on behalf of the defense or prosecution, expert witnesses are pertinent in a criminal trial. To read more about different kinds of expert witnesses and their specific roles, visit our informative blog pages below:

Tallahassee Criminal Defense Attorney

If you or a loved one has been accused of a crime, contact a qualified Tallahassee criminal defense attorney who will find a valuable expert witness to assist in your defense. Don Pumphrey and the members of the legal team at Pumphrey Law Firm are experienced in dealing with all kinds of criminal charges and will consult with knowledgeable expert witnesses in the field, such as the field of forensic toxicology, to ensure every applicable defense is explored in your favor. Call us today at (850) 681 – 7777 or send an online message today to discuss your legal matter during an open and free consultation with an attorney in our legal team.

Written by Sarah Kamide

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