Issue #1:  What are the major problems encountered in processing a drug-impaired driving case through the criminal justice system?

7.  Forensic toxicologists are not well prepared to testify as experts in DUID trials.

Many people practicing as forensic toxicologists come to the field with expertise in analytical chemistry, with limited training in the pharmacology of impairment in terms of drug impaired driving. The roles of the forensic chemist who performs or supervises the analysis of drugs in biological fluids are distinct from those of forensic toxicologists, who have the training and experience that qualifies them to interpret the results. Not all forensic chemists are necessarily qualified to go to court and provide interpretation of analytical results in impaired driving cases. Prosecutors also must critically assess the qualifications of their expert witnesses, and should not pressure witnesses to go beyond their areas of expertise.

The extent of the drug-impaired driving problem is still unknown. While there are growing but limited, resources for training and reference; there is also a lack of knowledge on the part of toxicologists about where to go to find the relevant information. Organizations such as the American Academy of Forensic Sciences (AAFS) and the Society of Forensic Toxicologists’ (SOFT) combined drugs and driving committee has done a lot to develop regular training opportunities for forensic scientists. Other programs such as Indiana University’s Center for Studies of Law in Action have also developed curricula in the effects of drugs on human performance and behavior. NHTSA supported an international consultative meeting of toxicologists in 2000, which resulted in the publication of Drugs and Human Performance Fact Sheets8. This is a concise resource on drug effects on driving. SOFT and AAFS, with support from NHTSA, have also developed detailed monographs concerning some of the priority drug groups for drug-impaired driving, published in Forensic Science Review.9

Forensic toxicologists often also have no ready access to the necessary medical and scientific literature, are not current with research developments in this field, and do not know what the standards of practice are, or what their peers are testifying to. Professional organizations and toxicology laboratory managers need to continue to promote training opportunities and to develop and distribute resource material. One missing resource is a listserv for peer consultation on drugs and driving issues. Another missing resource is a central Web site that would serve as a repository for publications, studies, fact sheets, and promote training opportunities. While groups such as the National Traffic Law Center10 (NTLC) also maintain lists of expert toxicological witnesses; however, this is not widely known and should be better publicized by professional organizations of prosecutors, toxicologists, and DREs.

In light of these considerations, the panel recommends that:

  • Expert testimony on the effects of drugs on driving should be the responsibility of forensic toxicologists with expertise in DUID, not forensic chemists. Academic and clinical toxicologists and pharmacologists often lack an understanding of the forensic context, and their testimony and opinions need to be carefully evaluated.
  • Individuals with expertise in behavioral science, pharmacology, pharmacodynamics, pharmacogenetics, neurological science, and drug effects should be encouraged to enter the field and become proficient in the forensic assessment of DUID.
  • Professional organizations in the forensic sciences must continue to provide training in pharmacology, pharmacodynamics, and drug effects to better develop forensic toxicology expertise in individuals who come to the field with a forensic chemistry background. These organizations can also contribute to training in trial testimony for their expert witness roles
  • NHTSA currently funds a traffic safety prosecutor fellowship position. They should also consider establishing and funding a similar toxicology position to act as a technical resource to the toxicology community.

8.  Prosecuting attorneys are ill-prepared to argue technical DUID evidence in court.

Most prosecuting attorneys arguing DWI and DUID cases are relatively inexperienced and can find the presentation of expert and scientific evidence intimidating. Due to large caseloads, their low comfort level with the issues and limited ability of the courts to try complex cases, many DUID cases get plea-bargained or dealt down to reduced charges. Most often more straight-forward cases involving alcohol are the ones that go to trial. Without a conviction for impaired driving, offenders do not get the sanctions their conduct merits, and incentives to change their behavior are correspondingly reduced, making them a continued menace on the roads.

Accordingly, this panel recommends that:

  • Prosecuting attorneys should be encouraged to spend more time with their expert witnesses – DREs and toxicologists – in preparation for trial. This small investment of time would improve prosecutorial understanding of the issues, reduce the amount of plea bargaining, and send a strong message about the seriousness of this crime.
  • Managers of attorneys prosecuting DUID cases need to provide better training to prepare attorneys for these cases. There are several existing resources for prosecutor training that should be further developed and disseminated. These include structured and transportable curricula from the NTLC, the National Association for Prosecutor Coordinators (NAPC)11 and trial advocacy courses at the National Advocacy Center. Additionally, DRE program staff and toxicologists from local laboratories are usually available and willing to assist with providing some form of local training, often at minimal or no cost.
  • Toxicology laboratories with expertise in DUID can take the lead in developing programs for outreach to local prosecutors, courts, judiciary, and law enforcement agencies through training, briefings, and by providing locally relevant fact sheets. Topics in successful programs have included education about the issue of DUID, guidance on testimony provided in DUID cases, laboratory polices for the receipt and analysis of specimens, and lists of resources available through the laboratory. Toxicologists, prosecutors and DREs need to take the initiative locally to establish better communication and share their knowledge and insight.

9.  Prosecuting attorneys don’t know where to turn for advice on presenting DUID cases.

While prosecuting attorneys can turn to the law enforcement officers and toxicology experts on their witness lists for advice and one-on-one training on the specific technical issues at hand in a DUID case, they often do not know who to turn to for advice on legal issues involving drugs and driving, or on the presentation of expert testimony. Predicate questions can be helpful but they have limitations as the most effective use of a witness is based on the specific circumstances of the case.

The American Prosecutors Research Institute’s National Traffic Law Center is a resource available to all prosecutors across the nation. Additionally 26 States currently have a designated Traffic Safety Resource Prosecutor, a position partially funded by NHTSA. This individual maintains a brief bank, helps to coordinate similar issues between jurisdictions, can provide lists of experts, organizes and participates in local training, and can assist in motions hearings. This panel recommends that this program should be expanded to all 50 States.

The State Traffic Safety Resource Prosecutor should also coordinate between local jurisdictions and national organizations such as the American Prosecutors Research Institute, which maintains a national brief bank, a database of toxicological and other experts, and other services.

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8 Couper, F.J., and Logan, B.K.  “Drugs and Human Performance Fact Sheets.” Washington, DC: NHTSA, Technical Report No. DOT HS 809 725 (June 2004).
This report can also be found on the NHTSA Web site at:

9 Forensic Science Review. 2002;14(1/2), and Forensic Science Review. 2003;15(1/2)

10 The National Traffic Law Center, American Prosecutors Research Institute, 99 Canal Center Plaza, Suite 510, Alexandria, VA 22314  Telephone: 703-549-9222

11 National District Attorneys Association, NDAA Headquarters, 99 Canal Street, Ste. 510, Alexandria, VA 22314  Phone: (703) 519-1682