Earlier this year, I attended the North Carolina Oral Fluid Summit sponsored by the Governor’s Highway Safety Program and the Foundation for Advancing Alcohol Responsibility. The focus of the Summit was roadside oral fluid testing for substances other than alcohol. It brought together law enforcement, advocates, and local government stakeholders to hear from experts on the science behind oral fluid testing, the experiences that other states have had so far, and what legal and policy considerations should be made before implementing roadside drug testing. An important note: the Summit was about roadside drug testing of people, not field testing unknown substances, which many law enforcement agencies currently use in investigations outside of the laboratory setting.
The two devices discussed most were the SoToxa Oral Fluid Mobile Test System and the Drager DrugTest 5000. A demonstration during the Summit of the SoToxa took about five minutes between the mouth swab and returning results, which tested for amphetamines, benzodiazepines, THC, cocaine, fentanyl, methamphetamine, and opiates. Both devices report a positive or negative result for each substance.
In North Carolina, instrument-based testing of people suspected of driving while impaired can be broken down into two areas: roadside testing and chemical analysis.
Roadside testing. Currently, the only roadside driver testing device regulated and authorized by statute is an alcohol screening test, also known as the portable breath test (PBT). Its implementation, upkeep, and evidentiary value are described in G.S. 20-16.3. For a test to be valid, it must comply with the regulations adopted by the North Carolina Department of Health and Human Services (DHHS). Section .0500 of Chapter 10A of the North Carolina Administrative Code lists the approved devices, calibration requirements, and administration procedure for roadside alcohol screening. When a test is properly administered, the fact that the driver showed a positive or negative result (or the fact that they refused) may be used by the officer and is admissible in court. It is admissible for determining if there are reasonable grounds for believing the person committed an implied consent offense, that they consumed alcohol, and if they had alcohol remaining in their body.
Chemical analysis. The chemical analysis of a person’s breath, blood, or urine is a more precise test, and may test for substances other than alcohol compared to the PBT. Blood and breath tests may yield a blood alcohol concentration, while blood and urine may be tested for substances other than alcohol. Procedures, admissibility, and evidentiary provisions are in G.S. 20-139.1. Like the PBT, any chemical analysis is also subject to the regulations adopted by DHHS in Subchapter 41B of the Chapter 10A of the Administrative Code.
A key difference between chemical analysis and roadside testing is the availability of implied consent testing for chemical analysis. When a licensed chemical analyst (sometimes the arresting officer or another certified individual) complies with the procedures set out in G.S. 20-16.2 in requesting a chemical analysis, a suspected impaired driver will be subject to an administrative penalty if they refuse. Along with the refusal being admissible in court, the person’s driver’s license must be revoked for one year. That said, implied consent procedures are not mandatory in order for a chemical analysis to occur. When law enforcement obtains a blood sample pursuant to a search warrant, for example, implied consent procedures do not apply.
Oral fluid testing. One of my takeaways from the Summit is how oral fluid testing has similarities to both roadside testing and chemical analysis. Like roadside testing, oral fluid testing is mobile and can be administered at the scene of an investigation, which is typically before an arrest. This means it could be administered before probable cause is established, as opposed to chemical analyses which are typically administered after arrest. Another similarity with roadside testing is that the tests discussed at the Summit only provide a positive or negative result for each substance. That said, like chemical analysis via blood, oral fluid testing involves the collection of a bodily substance by means of an intrusion (albeit a cheek swab rather than piercing the skin). Oral fluid testing also collects considerably more information about the person tested, including DNA and other molecules that contain information about the suspect that they may want to keep private and would be outside the scope of an impaired driving investigation.
Finally, a unique aspect of the devices discussed at the summit is that they target parent molecules, rather than metabolites. While metabolites may remain in a person’s system for days or weeks after substance use, parent molecules are only present immediately after substance use, and may provide a closer indication of whether the substance used is still causing an impairing effect. Before employing roadside oral fluid testing devices, the speakers emphasized the importance of examining what molecules are subject to detection and what the threshold levels are for a positive result. With this information, implementing agencies can endeavor to test for substances that indicate present impairment at a threshold amount that protects against false positive results.
Other states. At the Summit, we heard from representatives from Kentucky and Tennessee about the usage of oral fluid testing. Currently, most states that employ oral fluid testing use it the same way North Carolina uses the PBT. It is a roadside, confirmatory test that aids law enforcement in determining whether probable cause exists for impaired driving. The National Alliance to Stop Impaired Driving (NASID) has an interactive map that identifies oral fluid testing programs, enacting statutes, refusal penalties, and other chemical testing information per state.
What would North Carolina need? Because of the shared similarities, oral fluid testing would likely need to borrow from the legal and regulatory frameworks of both roadside testing and chemical analysis. A statute similar to G.S. 20-16.3 setting out the requirements, approval, manner of use, and evidentiary value of oral fluid testing would permit it to be implemented much in the same manner as the PBT. This would also require DHHS regulations specifically naming the approved devices, required training, calibration, and administration procedure for test results to be considered and/or admitted in court. One recommendation from the summit is to incorporate statutes or regulations addressing data collection and sample retention. Because roadside oral fluid testing may collect more information than the presence or absence of impairing substances, it may be preferable to include directives governing the destruction of the provided sample after the test is complete. At the same time, data collection that is anonymized can assist law enforcement agencies and other stakeholders in evaluating the usefulness and value of using oral fluid testing devices relative to the cost.
Roadside impact. Another takeaway from the summit was that in the states that have implemented roadside oral fluid testing, the testing has not replaced the work of Drug Recognition Experts (DREs). Rather, it has mostly aided law enforcement that are not DREs in determining whether to call or arrange for a DRE evaluation. More than one speaker emphasized that any implementation of roadside oral fluid testing depends heavily on the DRE capacity to conduct the DRE evaluation, because the roadside test only goes to the presence or absence of impairing substances and does not provide probative value about a person’s level of impairment. DRE evaluations that are properly administered, on the other hand, equip the DRE to testify as an expert on the issue of the person’s impairment, whether that impairment is caused by an impairing substance, and if it is, the category of impairing substance.
Final thoughts. The Summit underscored that roadside oral fluid testing is neither a cure-all nor a replacement for existing investigative tools, but rather a developing technology with the potential to aid drug‑impaired driving detection. Speakers emphasized that considerations of its adoption should proceed with attention to scientific validity, statutory language, and regulatory oversight. This would help ensure that implementation enhances public safety while preserving the integrity of the criminal justice process and the rights of individuals subject to testing. As I hear of any further developments in roadside drug testing coming to North Carolina, I will share what I can.
As always, feel free to reach out to me with any questions or comments. I can be reached at elrahal@sog.unc.edu.
