Related Experiment Videos
THC-influenced drivers in the new Danish 3-level offense system
Simon Kjær Hermansen1, Tina Ravn Pedersen1, Dorte Jensen Christoffersen1
1Section of Forensic Toxicology, Department of Forensic Medicine, Faculty of Health Sciences at the University of Southern Denmark, Odense, Denmark.
Traffic Injury Prevention
|December 11, 2019
Summary
A new Danish law reduced penalties for many tetrahydrocannabinol (THC)-impaired drivers, with 70% facing milder sanctions. Driving under the influence of drugs (DUID) cases continue to rise significantly.
Area of Science:
- Forensic Toxicology
- Drug-Impaired Driving Research
- Cannabinoid Analysis
Background:
- The study addresses the impact of a new Danish 3-level offense system for tetrahydrocannabinol (THC)-influenced drivers.
- Legislation changes on December 15, 2017, introduced graduated sanctions for driving under the influence of drugs (DUID).
Purpose of the Study:
- To analyze the distribution of THC-impaired drivers under the new Danish legal framework.
- To evaluate the consequences of the revised legislation on DUID offenses and sanctions.
Main Methods:
- Blood samples from suspected DUID cases in Funen and Southern Jutland were analyzed for THC concentration.
- Gas chromatography-mass spectrometry was used to quantify THC levels in whole-blood samples from 2,206 eligible cases between 2017 and 2018.
- Data were retrospectively extracted from laboratory information management systems to compare pre- and post-legislation periods.
Main Results:
- 70% of driving under the influence of cannabis (DUIC) suspects received milder sanctions following the December 2017 legislation change.
- The number of DUIC cases nearly doubled from 2015 to 2018 (648 to 1,206), and total DUID cases increased by 80% (898 to 1,614).
- THC was detected above the legal limit in 73% of cases, with 18% low, 32% medium, and 22% high concentrations.
Conclusions:
- The new graduated sanctions significantly impacted THC-impaired driving cases, with over two-thirds facing reduced penalties.
- There is a consistent and significant upward trend in DUID cases, indicating an ongoing public health and safety concern.
- Increased police vigilance, enhanced training, and improved roadside screening technologies likely contribute to the rise in detected DUID incidents.