The Drug Czar has been spending quite a bit of time focusing on the dangers of marijuana and driving. Tax dollars fund his Media Campaign, which includes a number of confrontational ads, including this one:
A boy walks across the street. He stoops down to add a snapshot to a collection of flowers, photos, and candles by the roadside.
Superimposed Text: His kid brother was killed... by a driver under the influence... of marijuana... He was the driver.
Voice Over: In a roadside study, one in three reckless drivers who were tested for drugs, tested positive for marijuana. It's more harmful than we all thought.
If you haven't seen this commercial (which would probably only be because you've been serving in Iraq, or have been living without a TV), you can watch it at Media Campaign (select "Super Bowl Memorial").
Here's the problem: If you do a little research through the Drug Czar's sites, you will discover that their entire support for this claim is based on the following study:
Brookoff, D.; Cook, C.S.; Williams, C.; and Mann, CS. Testing reckless drivers for cocaine and marijuana. New England Journal of Medicine 331:518-522, 1994.
This "study" basically followed a number of traffic stops in an area one summer. All those who appeared to be drunk were eliminated from the study (and no record was kept of how many were first screened out). Then the rest were tested for marijuana and cocaine (nothing else) with no testing for other drugs, fatigue, etc. There are so many problems here... But why listen to me?
According to the editors of the National Drug Strategy Network:
[This study has many fundamental methodological flaws. First, the basic data collection technique is flawed by eliminating an unknown number of suspected alcohol intoxicated subjects. Second, 28% of the 175 in the non-alcohol group were tested for alcohol and were positive for recent alcohol use at levels up to 0.21 mg/d l, a level far above legal intoxication. The authors point out that other studies have shown that up to one-third of subjects with blood alcohol levels in the intoxicated range have no appreciable odor of alcohol. Thus some of the intoxicated "drug" cases were certainly intoxicated by alcohol and probably not by use of cocaine or marijuana. The authors fail to correlate any of the alcohol intoxication data they had with either the drug use data or the degree of intoxication. Third, the authors fail to quantify or define "under the influence" and imply that it means testing positive for the drug metabolite in urine at any level of concentration. This indicates nothing about the level of impairment the person is experiencing. Nor does it tell us what drug is responsible for the impairment. In fact, the study states that some of those that were at first classified as not under the influence of alcohol but intoxicated later were found to have blood alcohol levels establishing legal intoxication and that some who tested positive for marijuana did not appear intoxicated. Fourth, the drivers could also have been under the influence of any number of prescription or over-the-counter drugs, for which the researchers did not test. While they tested positive for marijuana or cocaine or both, many other drugs (legal or illegal) could have been responsible for their impairment. This study falls prey to the fallacy that correlation equals causation. Not knowing the total number stopped for reckless driving makes it impossible to support the authors' conclusion that the use of marijuana and cocaine is a major cause of reckless driving. -- Editors]
So the TV ad does not demonstrate any legitimate scientific proof regarding marijuana and driving. But that doesn't deter John Walters. For example, the AP story Millions have driven while on drugs says:
An estimated 11 million Americans, including nearly one in five 21-year-olds, have driven while under the influence of illegal drugs, the government says...
John Walters, director of the White House Office of National Drug Control Policy, said the statistics show a failure to convince drivers that drugs impair driving as much as alcohol does. His office is kicking off an ad campaign to warn teens about driving while smoking marijuana.
"Marijuana is not the soft drug. Marijuana is not the casual rite of passage," Walters said at a news conference. "We have been sending the wrong message."
Notice how he says that the "statistics show a failure to convince drivers that drugs impair driving as much as alcohol does". Perhaps that's because, in the case of marijuana, it just isn't true!
Now, I don't recommend driving with any kind of impairment, whether it's drugs, alcohol, fatigue, or using a cell phone. But Walters is distorting the facts once again.
According to the National Highway Traffic Safety Administration study titled "Marijuana and Actual Driving Performance" (published November, 1993): "THC's adverse effects on driving performance appear relatively small." and "Evidence from the present and previous studies strongly suggests that alcohol encourages risky driving whereas THC encourages greater caution."
According to a 1994 Dutch study on "Marijuana Use And Driving" in real world conditions: "THC's adverse effects on driving performance appeared relatively small in the tests employed in this program."
A May 1998 Australian review of 2,500 injured drivers reported that cannabis had "no significant effect" on driving culpability."
A study conducted by the Transport Research Laboratory in 2000 was reported in the London Times article Cannabis May Make You a Safer Driver.
...researchers found that the mellowing effects of cannabis made drivers more cautious and so less likely to drive dangerously. Although the cannabis affected reaction time in regular users, its effects appear to be substantially less dangerous than fatigue or drinking."
The study's author Rob Tunbridge said:
"If you were to ask me to rank them in order of priority, fatigue is the worst killer, followed by alcohol, and drugs follow way behind in third."
The TRL study was repeated a year later and reported in New Scientist: Alcohol impairs driving more than marijuana, which confirmed that marijuana users, though mildly impaired in certain skills, adjusted by driving more carefully and alertly. The study also indicated that alcohol users gained some of that caution if they smoked marijuana.
According to the Canadian Senate's exhaustive 2002 report: "Cannabis: Our Position for a Canadian Public Policy," "Cannabis alone, particularly in low doses, has little effect on the skills involved in automobile driving."
But Walters doesn't care about the facts. He is pursuing his own agenda.
The Marijuana Policy Project is quite aware that Walters has declared his own war specifically on marijuana - ONDCP Ads Increase Teen Drug Use: Focus on Marijuana Ignores Problem of More Dangerous Drugs
"The Office of National Drug Control Policy is trying to change the topic with the new teen driving safety campaign," said Steve Fox, director of government relations for the Marijuana Policy Project. "By no means do we support anyone, particularly teens, driving under the influence of marijuana or other drugs, but ONDCP's continued focus on marijuana above all other drugs has made the problem worse. By concentrating on anti-marijuana scare tactics that are proven not to work and may even increase teen marijuana use, ONDCP is ignoring the increasing use of truly dangerous drugs like cocaine and heroin."
So, to sum up.
- People shouldn't drive while using marijuana
- Drivers should not be allowed on the road if they are impaired, whether that is from alcohol, drugs, or fatigue.
- There is, however, no evidence that marijuana use poses a significant danger on the road, certainly not in comparison to other impairments like alcohol.
- Adding drugged driving tests that only consider the existence of the drug in the bloodstream and not impairment, will not add to public safety, and may distract from real dangers
- The marijuana driving hype is another ploy by the Drug Czar to keep his drug war against marijuana users going strong and play on public fear.
