Beginning in the 1920s and lasting for seventy years, state and federal law treated marijuana as a dangerous drug and as contraband, forbidding its cultivation, distribution, possession, and use. Over the last two decades, however, numerous states have enacted laws permitting marijuana to be used for medical treatment. Some also permit its recreational use. Those laws have raised a host of novel legal and public policy issues. Most of the discussion, and almost all of the litigation, has involved the respective roles of the states and federal government and how each one may and should deal with this very controversial subject. One issue that has received little attention in the legal community is the risk that medical and recreational marijuana laws will pose to highway safety. Will those laws increase, decrease, or leave untouched the rate of accidents and fatalities on our nation's roadways? How should the criminal justice system--in particular, its law enforcement officers--address the problem of "drugged driving" in general and in states with medical marijuana laws? This Article addresses those issues. Some of the possible solutions do not involve changing the law. Training law enforcement officers to better spot drugged drivers, developing safe, reliable, portable, and inoffensive devices to test drivers for marijuana use on a highway shoulder, identifying a particular concentration of marijuana in the blood or some other bodily fluid that can be used to establish impairment--those and other steps can be taken without changing the legal framework for addressing the problems that occur when people drive under the influence of an intoxicating substance. But it also may be necessary to modify the laws governing alcohol in order to reduce the crashes caused by marijuana use. People often take those drugs in combination, and a marijuana-alcohol cocktail is more debilitating than either drug consumed alone. States therefore may need to lower their thresholds for drunken driving in order to dissuade people who use marijuana and alcohol together from getting behind the wheel.
TABLE OF CONTENTS INTRODUCTION I. THE INTERSECTION OF TWO IMPORTANT AND CONTROVERSIAL PUBLIC POLICY ISSUES A. The Debate Over Marijuana Legalization B. The Concern with Highway Safety II. THE EMERGENCE OF STATE LAWS AUTHORIZING THE MEDICAL AND RECREATIONAL USE OF MARIJUANA A. The Birth of Medical Marijuana B. The Birth of Recreational Marijuana C. The Effect of State Medical and Recreational Marijuana Initiatives on Highway Safety III. THE EFFECT OF MARIJUANA ON DRIVING A. The Effect of Marijuana Alone B. The Combined Effect of Marijuana and Alcohol IV. THE FRAMEWORK FOR ADDRESSING MARIJUANA-INDUCED DRUGGED DRIVING A. The Existing Framework for Alcohol B. The New Framework for Marijuana 1. Treating Driving Under the Influence of Drugs in the Same Manner as Driving Under the Influence of Alcohol 2. The Adoption of Zero Tolerance Laws V. A WAY FORWARD A. The Policy Proposals 1. Proposals that Do Not Require a Change in the Law 2. Proposals that Require a Change in the Law B. The Political Process CONCLUSION INTRODUCTION
Driving is a complex activity requiring alertness, divided yet wide-ranging attention, concentration, eye-hand-foot coordination, and the ability to process visual, auditory, and kinesthetic information quickly. (1) Although there have been reckless drivers for as long as there have been motor vehicles, psychoactive substances like alcohol can impair the driving skills of even the most careful Formula One racer. Operating a motor vehicle while under the influence of alcohol--known by the acronyms DWI, DUI, or OWI--demonstrably impairs the skills necessary for driving safely, making driving a hazardous activity. (2) Alcohol hampers tracking skills, attention, signal detection, hazard perception, reaction time, concentration, and hand-eye coordination. (3) It also reduces the perceived negative consequences of risk-taking. (4) Alcohol is also notorious for diminishing a person's driving skills even before he becomes aware of any impairment. (5)
Aware of the problems created by alcohol-impaired drivers early in the twentieth century, (6) states began to address the problem by prohibiting "driving while intoxicated" or "driving under the influence" of alcohol. (7) The states, however, did not stop there. By 2012, all fifty states and the District of Columbia adopted laws that deem driving with a specific blood-alcohol concentration level--0.08 grams per deciliter (g/dL)--as a crime. The effect of those laws is to render a driver with that BAC intoxicated as a matter of law, whether or not he was impaired in fact. (8) Those two sets of laws are a mainstay in the attempt to reduce mortality on our roadways.
Alcohol, however, is not the only drug that impairs a person's driving skills. Other psychoactive substances can also have that effect. As a result, over time states added various drugs to their statutes making it a crime to drive under the influence of alcohol. (9) One of those drugs is marijuana. (10)
Marijuana, a plant with an ancient origin, (11) is the third most commonly used recreational drug worldwide, after only alcohol and tobacco. (12) It also is the most widely used illicit drug despite having been under international control for eight decades. (13) Aside from the psychoactive effect of marijuana, two facts make its use particularly troublesome for highway safety: marijuana use is common among young people, (14) and young drivers account for a disproportionate share of traffic accidents. (15)
Until recently, society did not focus specifically on the problems caused by drugged driving. The federal and state governments made it a crime to manufacture, cultivate, distribute, and possess "controlled substances," including marijuana. The assumption was that, by outlawing cannabis, the criminal law would dissuade people from using it, whether or not they were driving.
Over the last few years, however, numerous states have revised their laws and now permit marijuana to be used for medical purposes. (16) Four states and the District of Columbia have gone even further and have decriminalized under state law the possession and use of small amounts of marijuana. (17) Those decisions complicate the question of how the criminal justice system should treat cannabis use. If that drug is not always and everywhere contraband, if it can be used for at least some purposes, the criminal justice system will need to address the distinct problems that arise when those new medical and recreational marijuana laws intersect with the statutes criminalizing reckless driving...