Marijuana, Other Drugs and Their Relation to Highway Safety: A Report to Congress [1980]

NHTSA · 1980 · ROSA P / United States. Department of Transportation. National Highway Traffic Safety Administration

archive: archived pipeline: cataloged verified

Get this paper ↗ (full text — opens at the source; we link to it, we don't host it)

Summary

This 1980 report by the National Highway Traffic Safety Administration (NHTSA) addresses the relationship between marijuana, other drugs, and highway safety, mandated by the Surface Transportation Act of 1978. The study aims to determine the frequency of drug use among drivers, assess law enforcement capabilities for detection, and evaluate federal and state prevention efforts. The report contrasts the well-established understanding of alcohol-impaired driving with the limited knowledge regarding other psychoactive substances, noting that while alcohol is a single substance with predictable effects, other drugs vary in complexity, duration, and detectability. The methodology involved a comprehensive review of existing epidemiological and experimental research, alongside data collection from federal, state, and local agencies. NHTSA contacted representatives across all fifty states, including police agencies, forensic laboratories, and health departments, to gather information on current practices and programs. The report synthesizes findings from chemical analyses of blood specimens from crash-involved and arrested drivers, as well as questionnaire-based surveys. However, the authors note significant methodological limitations, particularly the lack of valid comparison groups (non-accident-involved drivers) in epidemiological studies, which prevents definitive conclusions about the relative risk of drug-impaired driving. Key findings indicate that the extent to which drugs contribute to highway safety problems remains largely unknown. Epidemiological data show that psychoactive drugs, including marijuana, sedatives, and antianxiety agents, are present in drivers involved in fatal crashes or arrested for impaired driving, often in combination with alcohol. For instance, 16% of arrested drivers in one California study tested positive for THC, but only a small fraction tested positive for marijuana alone. Experimental studies confirm that various drugs can impair driving skills at certain dose levels. However, the report concludes that no drug other than alcohol has been established as a high-priority highway safety concern due to insufficient data. Law enforcement capabilities are limited by the lack of non-invasive detection methods (such as breath or saliva tests) for most drugs and by state statutes with significant loopholes. Only ten states had effective drug-and-driving laws at the time, and drug-impaired driving arrests were rare compared to alcohol-impaired arrests. The significance of the report lies in its identification of critical gaps in knowledge and enforcement. The authors conclude that roadside surveys of non-accident-involved drivers are essential to determine the true magnitude of the problem. Recommendations include revising state laws to align with the Uniform Vehicle Code, developing reliable non-invasive chemical tests, and establishing specific drug concentration levels that indicate impairment. The Department of Transportation proposed continued research into epidemiology, experimental effects, and behavioral testing, as well as the development of public information and education programs regarding the risks of driving under the influence of drugs.

Key finding

The extent to which marijuana and other drugs contribute to highway safety problems is currently unknown due to the lack of valid epidemiologic studies with adequate comparison samples.

Methodology

review

Provenance

The full processing record for this entry. Every stage of this paper's journey through the pipeline is logged — what ran, with which tool and model, how many attempts it took, and when it last completed. Discovered via bulk_ingest_rosap on 2026-05-23 (6 acquisition events logged).

Summary generated by qwen3.6-27b-prismaquant on 2026-06-10; verification: verified.

Topics

Ranked by relevance to this paper. Hover a topic for its definition.

• illicit drugs
• polydrug
• cannabis
• dui enforcement
• drowsy as impairment
• prescription meds

Information type

What kind of knowledge this paper contributes, grouped by family — independent of topic (what it is about) and method (how it was studied).

• Empirical Findings: observational prevalence