Drugged Driving Hopes

Federal officials announced a new effort to target motorists driving under the influence of illegal drugs. This may sound like a good idea to some, but it's half-baked with a bizarre twist -- the feds have paid researchers to test "drugged drivers" in real traffic.

White House Drug Czar John Walters and National Highway Traffic Safety Administration chief Jeffrey Runge announced the initiative at a Nov. 19 press conference.

Runge glibly justified the initiative by claiming, "NHTSA estimates that up to 22 percent of drivers involved in fatal motor vehicle crashes have tested positive for illegal drugs."

Runge should be pulled over for hyperventilating under the influence of false and misleading statistics.

NHTSA's estimate comes from the agency's October 2000 review of four limited studies on drug use and motor vehicle fatalities. NHTSA's review misrepresented the results of at least three studies. (The fourth study is an unpublished 1992 study by NHTSA staff that I could not obtain.)

A 1977 study of fatal accidents in Dallas County, Texas, reported drugs alone were detected in 9 percent of drivers. But NHTSA placed the drug detection level at 18 percent, misleadingly combining drugs-only detection with drugs-and-alcohol detection. None of the detected drug use involved marijuana; less than 1 percent was cocaine.

A 1982 study of 484 motor vehicle fatalities in Ontario detected drugs in 26 percent of drivers. But only 9.5 percent of drivers used drugs that might adversely affect driving skills. NHTSA went with the 26 percent drug detection level.

The third study involved 440 male drivers killed in California motor vehicle crashes. Although marijuana and cocaine were detected in 37 percent and 11 percent of drivers, respectively, "drugs were infrequently found alone; typically, they were found in combination with high blood alcohol concentrations."

The study's authors concluded, "Alcohol was associated with increased crash responsibility," but "the role of drugs [other than alcohol] could not be adequately determined."

NHTSA characterized the study as linking drugs with motor vehicle fatalities more than 40 percent of the time.

Most importantly, no study directly implicated drug use as a causal or contributory factor in the accidents. Researchers only considered the fact of drug detection, not the facts and circumstances of the drug use in connection with the motor vehicle accidents.

NHTSA's press release for the "drugged driving" initiative claims, "Over eight million persons aged 12 or older reported driving under the influence of illegal drugs during 2001."

Putting aside questions about how many 12- to 15-year-olds actually drive (much less truthfully admit to illegal drug use), NHTSA admitted in its October 2000 review that no research exists that has been "designed to provide an estimate of the extent of drug use by the general driving public."

"Previously, study populations have been selected from drivers who have either made an observed driving error, been injured in a crash, or been killed in a crash. Clearly, this is a select group that does not necessarily reflect the general driving population. A study is needed that can sample drivers in a more comprehensive fashion to gain a fuller and more accurate understanding of the prevalence of drug use in the general driving population as opposed to drug use in these select populations, " wrote NHTSA staff.

The bottom line is that the NHTSA "drugged driving" claims aren't worth the bodily fluid samples they're based on.

I'm not surprised at bureaucrats misrepresenting data to advance a political agenda, but I was surprised to learn the NHTSA's been sponsoring a "drugged driving" research program in the Netherlands -- where marijuana is legal and the rules for research involving human subjects are apparently more lax than in the U.S.

NHTSA paid Maastricht University researchers from 1998 to 2000 to study the separate and combined effects of marijuana and alcohol in real driving situations -- that is, with real traffic and pedestrians.

One test involved study subjects smoking marijuana and then driving 25 miles on public roads at 62 miles per hour at night!

NHTSA probably couldn't conduct such research in the U.S., where "drugged driving" testing has been limited to driving simulators and controlled courses.

I don't dispute that "drugged driving" occurs and should be discouraged. But it seems to be a much smaller problem than drunk driving. (I'd provide a statistic, but NHTSA's drunk driving numbers are faulty, too.)

Until NHTSA has a better handle on the extent of "drugged driving," the agency should avoid mission creep and focus its limited resources where it gets the biggest bang for the taxpayers' buck.

Steven Milloy is the publisher ofJunkScience.com , an adjunct scholar at the Cato Institute and the author of Junk Science Judo: Self-defense Against Health Scares and Scams (Cato Institute, 2001)

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