This paper presents some results of a study, by the National Institute of Forensic Technology, Oslo, of the frequency of multi-drug use and the most common drug combinations used by suspected drugged drivers. It also considers which forms of multi-drug use occur more frequently in drivers involved in traffic accidents. In 1991, the Institute received 2352 blood samples from suspected drugged drivers. Samples with blood alcohol concentration (BAC) above 0.05%, or above 0.15% for cases reported as road traffic accidents, were excluded. Drug analyses were completed for 1514 samples included in this study. For 411 cases, the police also asked for an expert witness statement. These cases were divided into three subgroups, based on the reason for arrest reported by the police: (1) traffic accidents; (2) reckless or dangerous driving; (3) others. Various results were compared for these subgroups. The following results are summarised: (1) drug findings and multi-drug detection; (2) benzodiazepams (BZDs) and impairment; (3) drug detection in road traffic accidents, compared with non-accident cases; (4) main drugs responsible for possible impairment; and (5) age and sex distribution. The study shows that BZDs and THC (cannabis) are used by most suspected drugged drivers in Norway.
Abstract