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Toxicology

Contents:


Toxicology is the study of the effects of drugs on biological systems. Specifically, forensic toxicology focuses on the detection of alcohol, drugs, and other toxic substances in the human body. The State Crime Laboratory currently uses screening and confirmatory tests to indicate the presence of a drug in a defendant’s blood, urine, or other bodily fluids. For information about the identification of bulk samples of suspected controlled substances, click here. This page was created in August 2014. Attorneys should check that the lab procedures referenced are the most up-to-date versions.

Procedures for Testing Bodily Fluids for Drugs

Toxicology samples that are being tested for drugs are screened using a presumptive test, such as the ELISA test. If the screening yields a positive result, the sample must undergo an extraction and be tested using a confirmatory test to conclusively identify the substance that is present and potentially quantify the amount of the substance that is present.

  • Presumptive Test
    1. ELISA Immunoassay
  • Identification and Quantification
    1. Extraction
    2. Identification and Quantitation
  • Link to the State Crime Lab’s procedure
  • Characteristics:
    • ELISA can be performed on blood and urine.
    • Immunoassays measure the presence or concentration of a substance in urine or other fluid by using antibodies that specifically bind to drugs and their metabolites (the compounds that form after the body has metabolized a drug).
  • How it works:
    • An antigen is a foreign substance that induces an immune response by triggering the production of an antibody.
    • In immunoassays, antibodies that contain enzymes react and bind to a specific drug or drug metabolite. This reaction generally produces a signal, such as a color change, or can be measured using other methods of measuring enzyme activity.
  • Substances it tests for:
    • in blood:
      • Barbiturate
      • Benzodiazepines
      • Carisoprodol
      • Cocaine Metabolite (Benzoylecgonine-BE)
      • Cannabinoids (THCA/CTHC)
      • Methadone
      • Methamphetamine
      • Opiates
      • Tramadol
      • Zolpidem
      • 3,4-methylenedioxymethamphetamine (MDMA)
    • in urine:
      • Barbiturate
      • Benzodiazepines
      • Cocaine metabolite (Benzoylecgonine-BE)
      • Methadone
      • Methamphetamine
      • Opiates
  • Results:
    • Understanding how the laboratory reports results is imperative. The State Crime Laboratory reports results stating that a specific drug or classes of drugs are positive or negative. These results must be confirmed by a confirmatory test.
    • ELISA immunoassays measure the color change that occurs when a sample tests positive for a specific drug. The State Crime Laboratory uses the Tecan/Immunalysis Freedom EVO ELISA Analyzer to measure the color change. This machine measures the color change by determining how much light is absorbed by the sample, also known as the absorbance.
    • Absorbance and concentration are inversely related. If a sample’s absorbance is low, the concentration of the drug present in the sample is higher. If a sample’s absorbance is high, the concentration of the drug present in the sample is lower. (See Section 5.8). This chart demonstrates how results are reported:
Analysis
  • All results that test positive or elevated will continue to confirmation testing, including extraction and either GC/MS or LC-MS/MS analysis.
  • Limitations:
    • Because immunoassays are only screening tests, positive results must be confirmed using a confirmatory test.
    • False positives with are possible. This website lists the cross reactivities of some drugs. Another list of cross-reactivities is available here.
    • ELISA testing for cannabinoids cannot be performed on urine samples and will only be performed on blood samples.
  • Links:
    • This video demonstrates how an ELISA test is performed and how the science works.
    • This website provides and in-depth explanation of the science of the ELISA test.

Blood and urine contain a wide variety of compounds. Confirmatory tests (GC/MS, LC-MS/MS) cannot be performed on whole blood or urine samples since there are too many compounds. Some compounds may interfere with the machine’s ability to interpret the presence of a substance of interest. To solve this problem, prior to confirmatory analysis, the analyst must perform an extraction to isolate the testable portion of the sample. An extraction is scientific technique that separates immiscible compounds (ones that do not mix easily) based on their solubilities. The State Crime Laboratory uses both liquid-liquid extraction and solid phase extraction in their procedures. Those procedures are described below:

  • Acidic/Neutral Drug Solid Phase Extraction (ANSPE)
    • This procedure is to be used for extraction of acidic, neutral, and basic drugs from blood, serum, and urine.
    • It should not be used for cannabinoids or phenethylamines.
    • The sample will be separated into acidic/neutral and basic fractions via an extraction column.
    • Typically, the acidic/neutral fraction will contain barbiturates, carisoprodol, meprobamate, and some benzodiazepines. Alkaloids, amphetamines, opiates, zolpidem, tramadol, and most benzodiazepines elute in the basic fraction.
    • Some compounds may need to be further separated by derivatization. The technique of derivatization does not change the drug being tested, it only removes the insignificant ions that interfere with GC testing.
    • Morphine and benzoylecgonine are examples of drugs that need to be derivatized for detection. Some benzodiazepines will need to be derivatized if they already screened as positive or elevated in a sample and no corresponding signal was detected in subsequent GC/MS testing.
  • Phenethylamine Liquid-Liquid Extraction (PHEALLE) for Analysis by GC-MS – This procedure is to be used to extract phenethylamine drugs (such as methamphetamine, MDMA, amphetamine, ephedrine, or pseudoephedrine) from blood or urine.
  • Blood Cannabinoid Liquid-Liquid Extraction (BCLLE) for Analysis by LC-MS/MS – This procedure is to be used for extraction of cannabinoids from a blood sample. This procedure is not to be performed on urine samples. This test is used to test for presence of THC, THCA, and 11-OH-THC.

Once the desired portion of the sample is isolated it is then conclusively identified and if appropriate, quantitated. The State Crime Laboratory tests blood, urine, and serum using two methods: Gas Chromatography/Mass Spectrometry (GC/MS) and Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS).

  • Gas Chromatography/Mass Spectrometry (GC/MS)
    • This technique is used after an extraction performed using the PHEALLE (liquid-liquid extraction) method or solid phase extraction method.
    • For more information about the science behind GC/MS, how a GC/MS works, and the limitations/considerations of GC/MS testing, click here to be redirected to the NCIDS Drug Analysis page.
    • Toxicology-specific limitations/considerations of GC/MS testing:
      • Subtraction: The State Crime Laboratory’s procedure for Toxicology GC/MS testing allows for the analyst to subtract interfering signals from the chromatogram. (See Section 5.6.12.2.4.) The procedure proscribes that when additional major ions are present, the source of the extraneous, background ions may be subtracted prior to formal analysis (peaks may be removed from the chromatogram to better visualize the remaining peaks, which are then compared to known reference standards). Only a trained expert will be able recognize if and when an essential peak has been erroneously subtracted and should be consulted as needed.
      • The State Crime Laboratory Procedure lists its criteria for a positive match for GC/MS data in Section 5.6.12.2 and 6.6.12.3. These criteria include:
        • The mass spectrum shall be compared to reference mass spectra.
        • Probability Based Matching (PBM) is a computer-calculated figure that represents the probability that the peak of interest matches the reference peak. Ex. Unknown peak has 98% probability of matching cocaine. PBM shall be used to aid in identification but should not be used as the sole means of identification.
        • The mass spectrum must contain all of the major and diagnostic ions unique to the analyte.
        • The signal to noise ratio (the response at the baseline or valley immediately before the internal standard signal) of the internal standard must be greater than 5:1.
        • To be considered a match, the ion’s retention time must be within 2% of the reference standard’s retention time.
        • This method is not to be used to distinguish between optical isomers.
  • Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
    • This technique is used only in conjunction with the BCLLE extraction method, for blood cannabinoid testing. The State Crime Lab’s procedure is available here.
    • How it works:
      • Liquid Chromatography (LC) is similar to Gas Chromatography (GC), except that the mobile phase used to separate molecules is a liquid instead of a gas. Molecules are separated by a liquid mobile phase so that they can be analyzed after separation by a mass spectrometer.
      • Tandem Mass Spectrometry/Mass Spectrometry (MS/MS) is the technique used here to further separate the molecules into measurable fragments. When a molecule travels through the mass spectrometer, and breaks apart, the resulting pieces are called fragments. The fragments are measured by the detector at the end of the mass spectrometer which creates peaks on a mass spectrum. A higher volume (number) of a specific fragment will generate a higher peak on a mass spectrum. The size and position of the peaks on a mass spectrum will exclusively identify unknown compounds. Tandem mass spectrometers have more than one analyzer that operate simultaneously and further separate complex molecules into more defined fragments. See the Drug Analysis page for additional explanation of the science of mass spectrometry. Tandem MS/MS analysis is specifically used for determining the structure of a molecule, while MS alone is used to determine the molecular weight of the molecule. Tandem mass spectrometry can be used to distinguish between molecules that are very similar.
    • Limitations:
      • The State Crime Laboratory procedure warns that this procedure shall not be used to distinguish between optical isomers. See Section 6.1.
      • A calibration curve must be generated for quantitation of THC present in the sample. The procedure lists when to accept or reject the calibration curve. See Section 5.6.3.2.
      • The positive control must be within 25% of the expected concentration. See Section 5.6.4.1.
      • The State Crime Laboratory’s procedure permits manual integration of a some peaks. See Section 5.6.5. The analyst must attach the paperwork accompanying the manual integration in the laboratory packet. Manual integration should only be performed under appropriate circumstances. Only a trained expert can recognize when a manual integration should or should not have been performed.
      • All body fluids must be homogeneous (same throughout). The blood/urine/serum must be well-mixed prior to sampling (taking an aliquot) so that what is taken from the sample is representative of the entire sample. If a homogeneous sample cannot be obtained, the procedure requires that this be noted in the report. See Section 5.4.
      • The internal standard must be within 50% to 200% of the average internal standard range. See Section 5.7.2.
      • Typically, if a batch fails, the analyst will repeat testing on a new aliquot. If not enough sample remains, the failed batch data may still be reported if certain criteria are met. See Section 5.7.3.

Procedures for Testing Blood for Alcohol

The Toxicology Section at the State Crime Laboratory performs Headspace Gas Chromatography to both confirm the presence of alcohol and quantitate the amount of alcohol present in a blood sample.

  • Link to the State Crime Lab’s procedure
  • Characteristics:
    • GC Headspace is not an altogether different method of toxicology analysis, but simply just a different way of introducing the sample into the machine.
    • Volatile liquids (such as alcohol) are favorable types of samples to be tested with GC Headspace.
  • How it works:
    • The analyst will fill a GC vial with a proscribed amount of the Internal Standard Solution and the blood sample and seal the vial with a cap.
    • The Internal Standard Solution contains ethanol, methanol, isopropanol, and acetone. It is added so that the analyst can later compare the peaks produced by the known amounts of these standards with the peaks produced by the evidence sample.
    • The volatile analytes (ethanol, methanol, isopropanol, and acetone) will begin to vaporize inside the vial (similar to a carbonated drink building up pressure in a sealed bottle.)
    • The vial will contain a layer of blood at the bottom and a layer of gas on the top called the headspace. After time, headspace will have equilibrated (the contents of the gaseous layer will be equally distributed throughout that layer) and the headspace can be tested by the machine.
    • The machine will draw a sample for testing from the headspace. The headspace gas sample will continue through the gas chromatograph as described in the gas chromatography section of the NCIDS Drug Analysis webpage. See this video for additional explanation of headspace sampling.
    • After the headspace sample is separated into its component parts by the gas chromatograph, the components will enter the Flame Ionization Detector (FID) which measures the amount of analyte present. A hydrogen flame will cause the organic compounds in each component to combust. The strength of the combustion is proportional to the amount of the organic compound present and is measured by the height of the flame. The height of the flame will be represented as a peak on the resulting graph.
    • This animation demonstrates how a flame ionization detector works. Note that the animation involves a liquid sample rather than a headspace sample.
    • Identification of ethanol is determined by comparison of its retention time with the retention time of a known standard in the Internal Standard Solution.
  • Limitations:
    • GC Headspace primarily tests for the presence of alcohols (ethanol, methanol, and isopropanol) and acetone. For quantitation purposes, a calibration curve must be made for each analyte.
    • The blood is sampled and tested four times (in replicate). Each run will have a resulting concentration of all four analytes. Therefore, there will be a total of 4 resulting concentrations for each analyte. The four concentrations are averaged and reported as a mean. See Section 5.6.3. If any of the requirements below are not met, then the sample must be reanalyzed:
      • Each of the four concentrations for ethanol must be within 6% of the mean.
      • Each of the four concentrations for methanol must be within 9% of the mean.
      • Each of the four concentrations for isopropanol must be within 8% of the mean.
      • Each of the four concentrations for acetone must be within 20% of the mean.
    • No further analysis is performed on DWI submissions where the BAC was found to be 0.08 g/100 mL of whole blood unless:
      • The case involves the death or personal injury of someone other than the driver of the vehicle.
      • Upon approval of a request from the District Attorney’s office. See Section 6.2.
    • Homogeneous samples are required for analysis. If a homogeneous sample cannot be obtained due to clots, blood cells becoming separated from the liquid, or other reason, the concentration must be converted to whole blood alcohol concentration by dividing the alcohol concentration by 1.18 to compensate for the water present in the sample. See Section 6.1.

Reports and Publications

From the Blog

  • THCA: One Abbreviation, Two Compounds, 10/13/2021
    Have you received a lab report in a DWI case where blood is tested by the State Crime Lab for cannabinoids? If so, the report probably had a section that looked like this: When forensic labs test blood for marijuana, they test for the presence of delta-9-tetrahydrocannabinol (THC), which is the primary psychoactive component of …
  • The effect of contextual information on decision-making in forensic toxicology, 7/26/2021
    This recent study by Dr. Hilary J. Hamnett and Dr. Itiel E. Dror looked into the possible effects of contextual case information in forensic toxicology testing. Two experiments were conducted in this study. The first focused on the interpretation of immunoassay screening data and the error rates of the participants’ conclusions. The participants were asked …
  • Field Sobriety Tests and THC Levels Unreliable Indicators of Marijuana Intoxication, 6/19/2021
    National Institute of Justice-supported researchers from RTI International recently published the results of their research showing that field sobriety tests and THC levels are unreliable indicators of marijuana intoxication. The full study can be read here. A summary of the research is available here and provided the following take-aways that will be of interest for …
  • Nationwide vacutainer recall raises doubts about blood alcohol tests, 8/1/2019
    An announcement from Becton Dickinson and Company (BD) may raise doubts about the validity of some blood alcohol tests conducted across the country since August 31, 2018. On May 30, 2019, with a correction made June 12, 2019, BD announced a recall for its “BD Vacutainer® Fluoride Tubes for Blood Alcohol Determinations” product. Vacutainers are …
  • ANSI/ASB Best Practice Recommendation 037, Guidelines for Opinions and Testimony in Forensic Toxicology, 1/29/2019
    The American Academy of Forensic Science Standards Board (ASB) has published ANSI/ASB Best Practice Recommendation 037, Guidelines for Opinions and Testimony in Forensic Toxicology, First Edition. This document delineates guidelines for best practices in forensic toxicology opinions and testimony, including human performance toxicology (e.g., driving under the influence of alcohol or drugs), postmortem forensic toxicology, …
  • OCME Toxicology Lab Procedures available, 9/18/2018
    The IDS Forensic website has posted the toxicology lab procedures from the NC Office of the Chief Medical Examiner here. Attorneys who would like to learn more about the procedures that the OCME toxicology lab uses to test evidence can read through the procedures. For casework, attorneys should obtain the lab procedures that were in …
  • Houston in the Blind, 5/8/2018
    Blind studies and procedures are the gold standard of evaluating the quality and reliability of scientific results. Unfortunately, this has long been lacking in forensic science. Fortunately, strides are being made to introduce blind testing to forensics, most notably in the Houston Forensic Science Center (HFSC). Currently, forensic scientists are tested periodically on their knowledge …
  • Mass. Supreme Court Considers Relevance of FSTs for Marijuana Impairment, 11/29/2017
    Any practitioner that handles driving while impaired charges knows the significance of field-sobriety tests (“FSTs”) to the investigation and prosecution of drunk driving. Scientific research supports the basic idea behind the tests — that test performance on FSTs is an indicator of alcohol impairment. What about when the impairing substance isn’t alcohol at all? Do …
  • Toxicology Testing by NMS Labs – FAQ, 7/22/2016
    Many attorneys have asked us about blood-drug (and some blood-drug and alcohol) testing performed by NMS Labs. We have compiled the questions and our answers here. If you have additional questions, please post them in the comments and we will try to answer them as well. Let’s make this a living document! The toxicology evidence …
  • Reliability Concerns Regarding Probation Drug Screens, 8/12/2015
    The NC Department of Public Safety (DPS) has begun relying on less accurate presumptive testing for urine screens for drugs for probation, prison, and DSS cases. The focus of this post will be probation cases, though the testing is the same for prison and DSS cases. Testing Prior to 2014 Until February 2014, the Department …
    • Click here for more blog posts on this topic

Trainings

  • Forensic Evidence and Current Concerns in the Criminal Justice System
    Virtual program offered by John Jay College of Criminal Justice. Reg. $150
  • NCAJ’s Criminal Masters in Advocacy 2021: Expanding Your Litigation Toolbox, NCAJ
    Virtual CLE offered by NCAJ
  • Investigation and Certification of Drug Toxicity Deaths in Today’s Complex Drug Environment, CFSRE
    Free webinars offered by CFSRE
  • THC/Cannabis – Recognizing Impairment, NAPD
    NAPD webinar
  • Defending Drug Overdose Homicides Training, NACDL
    Live webinar, Sponsored by NACDL
  • Forensic Toxicology: Methods Used and Common Errors in Screening and Confirmatory Tests

    NC criminal defense and parent attorneys and their investigators may register for the program using this link.

    This five-hour live webinar on Nov. 19-20, 2020 will provide attorneys having little science training with the basics about the various forensic toxicology principles and techniques employed by forensic laboratories, contract labs, and probation officers around the country. We will cover basic pharmacology/toxicology, drug screening and monitoring tests frequently used in probation and DSS cases as well as instrumentation methods that may be used to confirm the results of screening tests.  

    Attendees will be provided with a clear foundation about these concepts and methodologies, their utilities and limitations, learn how to identify the key information in drug test reports from various labs, and will be challenged with interpreting hypothetic case examples. This training will aid in the understanding of the forensic evidence in cases involving suspected use of controlled substances.

    Agenda:
    Nov. 19, 2020
    1:00-3:30 pm Drug behavior in the body and field drug testing (Dr. Andrew Ewens)
    3:30-4:00 pm Q&A

    Nov. 20, 2020
    1:00-2:00 pm Laboratory drug testing – Validity, screening, confirmation, and quality assurance (Dr. Kiran Dhakal)
    2:00-2:30 pm Drug test reports and case examples (Dr. Andrew Ewens)
    2:30-3:00 pm Q&A

    Speakers:

    Kiran Dhakal, Ph.D., DABT
    Ph.D. in Human Toxicology, post-doctoral training in neurotoxicity of organophosphate warfare agents, Board certified in Toxicological chemistry (NRCC) and Diplomate of the American Board of Toxicology (DABT), clinical and forensic toxicology research experience using Mass Spectrometry, works as a part-time lab director and consultant for clinical and forensic toxicology labs. Experience in interpretation of toxicology laboratory results.

    Andrew D. Ewens, Ph.D., DABT
    Doctorate degree in pharmacology and board-certified in toxicology with 25 years of experience covering a broad range of areas within pharmacology and toxicology, 10 years of experience conducting research, 8 years working on legal cases, interpreting drug use, drug-induced impairment, and drug-induced cause of death, as well as providing drug testing services. Cases include murder/assault, cause of death, DUI/retrograde extrapolation, probation violation, post-conviction, personal injury, child custody, medical malpractice, and employment drug testing. Qualified as an expert to testify in North Carolina, Texas, Maryland, and Michigan. Conducting research based on previous legal cases, covering topics such as SFST/DRE evaluations, sources of mouth alcohol, false positive testing from CBD use, and source of the “alcohol” breath smell, developing a new drug detection device, as well as developing a treatment for athletes’ foot. Previous research includes developing an immunotherapy treatment for cancer that cures mice of lymphoma and breast cancer and developing a new technique for detecting chromosomal damage. Has worked as a contract toxicologist for 15 years with 5 federal agencies, including the National Toxicology Program, which is an joint interagency effort by the NIH, FDA, and CDC, three institutes within the National Institutes of Health (National Institute of Environmental Health Sciences, National Library of Medicine, and National Cancer Institute) as well as the Centers for Disease Control and Prevention, and Environmental Protection Agency.

    Volunteered with the Cary Community Emergency Response Team where he received training from the Raleigh Fire Department in Hazardous Materials response up to the level of HazMat Technician and taught classes on responses to terrorist attacks and hazmat response. Also volunteers with the Cary Citizens Assisting Police where he provided support for a DWI checkpoint and assisted in testing bomb detecting dogs for the Transportation Security Administration.

  • Southwestern Association of Forensic Scientists 2020 Virtual Conference, FTCOE

    This free virtual conference will cover topics including seized drugs, toxicology, DNA, and more.

  • Free Webinar: DRE (Drug Recognition Evaluations) & ARIDE (Advanced Roadside Impaired Driving Enforcement) — Their Purpose, How Are They Different, How to Discredit Them, NACDL
    Speakers: Doug Murphy, Tony Palacios, and Steve Oberman. Offered by NACDL and NCDD.
  • Current Trends in Forensic Toxicology Online Symposium

    This free online program is hosted by the Center for Forensic Science Research & Education (CFSRE) and organized by practitioners from the forensic community. It offers in-depth, 1-hour lectures on a variety of topics, panel discussions, and a week-long poster session. In addition to the live event, all presentations are recorded for on-demand viewing and cataloged in the Symposium Proceedings e-book.

    • June 8th, 2020 – Day 1: Postmortem changes
    • June 9th, 2020 – Day 2: Inter-individual variations and toxicology interpretation
    • June 10th, 2020 – Day 3: Innovations in analysis
    • June 11th, 2020 – Day 4: Challenges of cannabis and cannabinoids
    • June 12th, 2020 – Day 5: Court testimony
  • Forensic Epidemiology: Monitoring Fatal Drug Overdose Trends, FTCOE

    The Forensic Technology Center of Excellence is offering this free webinar program.

    Given the vital role of medical examiners and coroners (ME/C) in recognizing emerging trends in drug overdose deaths, partnering epidemiologists with ME/C offices can greatly enhance the utility of the significant volume of data generated by medicolegal death investigation. Epidemiologists from three unique ME jurisdictions—North Carolina, New Mexico and Virginia—share their experiences with monitoring drug overdose deaths, trends observed, and how best to utilize ME/C data to inform public health policy.

    Detailed Learning Objectives:

    1) Describe the potential role of epidemiologists in medical examiner offices and how they can assist in utilizing medicolegal death investigation data.

    2) Understand current trends in drug overdose deaths as analyzed by three large statewide ME jurisdictions.

    3) Understand the challenge of balancing state-mandated priorities with research and public health outreach.

    Speakers:
    Dr. Sarah L. Lathrop
    Alison Miller
    Kathrin ‘Rosie’ Hobron

  • Current Trends in Forensics & Forensic Toxicology

    2nd Annual Online Symposium hosted by RTI and ForensicEd on May 13-17, 2019. This program offers information on best practices in forensic toxicology, drug analysis, and trace analysis such as sample preparation, method development, and forensic method validation. Presentations are geared toward forensic practitioners, but several of the sessions should be of interest to attorneys.

Websites

  • Forensic Toxicology Resources

    Lists numerous websites, webinars, and other helpful online resources, prepared by Peter Stout, Ph.D., D-ABFT

  • Clinical Laboratory Improvement Amendments

    The CLIA program works to ensure quality laboratory testing in all clinical laboratories regulated by the Centers for Medicare and Medicaid Services.

  • American Board of Forensic Toxicology

    The ABFT is a non-profit organization certifies forensic toxicologists and accredits forensic toxicology labs that comply with standards of the ABFT.

  • Society of Forensic Toxicologists

    SOFT is an organization of practicing forensic toxicologists. SOFT’s annual meetings provide a forum for the exchange of information and ideas among toxicology professionals. SOFT sponsors workshops, newsletters, proficiency testing, and technical publications with the goal of improving toxicologists’ skills and knowledge. These Forensic Toxicology Laboratory Guidelines by SOFT and the American Academy of Forensic Sciences provide basic requirements for forensic toxicology labs, including guidelines on the use of screening versus confirmatory tests.

  • Florida Forensic Science

    A collaboration between the Orlando Public Defender and the National Center for Forensic Science at UC Florida. The site has links to many helpful training videos that help attorneys understand forensic science evidence.

  • A Simplified Guide to Forensic Science

    The National Forensic Science Technology Center created this website to explain in simplified terms the principles of each type of forensic analysis and how the analysis is performed. Topics include DNA, digital evidence, fingerprints, firearms, trace evidence, blood stains, and more.

Cases

  • State v. Teesateskie (2021)

    The defendant also argued on appeal that the trial court should not have allowed the State’s expert to testify as to possible reasons why Hydrocodone did not show up in the defendant’s blood test, because that testimony violated Rule 702 in that it was not based on scientific or technical knowledge, was impermissibly based on unreliable principles and methods, and was prejudicial due to the stigma associated with Hydrocodone on account of the opioid crisis. The Court of Appeals concluded that even if the issue was properly preserved for appeal, and even if the admission of the expert’s statement was an abuse of discretion in violation of Rule 702, it was not prejudicial given the defendant’s admission that she took Hydrocodone before the accident.

  • State v. Pabon, 850 S.E.2d 512 (2020)

    A SCL analyst testified to the results of another analyst’s testing. However, he personally reviewed the data and offered his own opinion, which the court held did not violate the Confrontation Clause. 

  • State v. Echols, 845 S.E.2d 208 (2020) (unpub)

    Dr. Wilkie Wilson’s testimony on decedent’s behavior being consistent with methamphetamine intoxication violated Rule 702(a)(1), where he had not examined the decedent and based his opinion on witness statements and a medical report from 2014.

Motions and Briefs

Toxicology Experts