I attended an Advanced DRE/Green Lab course in November, sponsored by Chris Halsor of Understanding Legal Marijuana, LLC. The course catered to Drug Recognition Experts (DREs) wishing to learn more about marijuana-impaired driving: how to detect it and to document and present evidence in court to achieve convictions. It included lectures, visits to marijuana dispensaries and a grow facility, and a green lab that provided an opportunity to question and evaluate regular daily marijuana users in a non-threatening environment. The highly interactive session enabled experienced DREs from many states to share their knowledge with one another, further increasing the value of the course.
The session I attended included a prosecutor, a NHTSA regional administrator, and DREs from four states. Participants ranged from inexperienced DREs to ones who had performed over 4,000 evaluations. One DRE was moving to emeritus status.
Five daily marijuana users volunteered as subjects for the green lab, the highlight of the course. Duration of use ranged from a few years to over thirty years; intensity ranged from one joint per day to “all day long”, frequently combined with the use of edibles. All were employed and very cooperative. Upon arrival, each volunteer had his/her vital signs recorded by a paramedic and then met with an interview team for a half- hour. Each interview team consisted of a lead interviewer, a note-taker, and a videographer. The interview included some roadside sobriety tests, an oral fluid test and further vital signs, but focused on questioning techniques. After a marijuana-dosing break, each volunteer met with a different interview team for a repeat performance.
Volunteers were not required to arrive sober. “Hey, it’s my day off!” All tested positive for THC in oral fluid before and after the dosing break. This makes sense with known understanding of how long marijuana components remain in the body, and you can Click here for more information regarding that. The volunteers tested negative for other substances (cocaine, opiates, benzodiazepines, amphetamines). Some were judged to be impaired in the first interview. All were judged to be impaired during the second interview. Some admitted to being unsafe to drive, while others said they could drive safely and have driven in that condition before. So no wonder people were impaired during the second interview.
The non-threatening environment enabled DREs to pose questions not possible in an arrest situation and enabled an openness on the part of the marijuana users that cannot exist after a traffic stop. Several of the volunteers had participated in prior green labs, indicating they found the experience to be both valuable and non-intimidating.
Knowing that Standardized Field Sobriety Tests (SFSTs) are only modestly successful in identifying stoned drivers who are frequent users, I was impressed seeing the power of SFSTs and other less well-established tools to identify and quantify impairment of all of our five volunteers. DREs are highly trained observers, and those on my team occasionally pointed out impairment cues that I, as an un-trained observer, had not noticed on my own. I can see where SFSTs in the hands of less qualified officers might be less powerful.
In addition to learning a good deal, I came away with the following impressions:
- Marijuana by itself can impair driving ability, and by more than some users might admit.
- DREs are a highly professional, capable resource that are not easily duplicated.
- Bud tenders and others working in dispensaries make it easy for the novice to be introduced to today’s huge variety of marijuana products.
- Marijuana commercialization, although in its infancy, is already highly sophisticated.
- Better tools are needed for officers to identify and quantify drug impairment based on driver performance, rather than lab testing.
- Training classes such as this can increase officers’ professional skills. Halsor also offers An Introduction to Marijuana DUI Investigations for non-DRE officers to better equip them for detection on the street.