Drugged Drivers Outnumber Drunk Drivers 7.4 to One on Weekend Nights

The latest National Highway Traffic Safety Administration (NHTSA) survey has found that 2.2% of drivers on the highway weekend nights were intoxicated and 16.3% tested positive for drugs.

The survey involved almost 11,000 randomly selected drivers at 300 locations across the United States. When the same survey was conducted in 1973, 7.5% of such drivers had a blood alcohol concentration (BAC) level of .08 or higher. The drop to 2.2 is a decline of 71% since the earlier survey.

The percentages drunken drivers found in all four national roadside surveys of weekend night drivers can be seen in figure 1.

Figure 1
Figure 1: Percentage of Weekend Nighttime Drivers with BACs ≥ .08 g/dL in the Four National Roadside Surveys

The most recent survey is the first of to test for drugs. The most common illicit drugs used by drivers were marijuana or THC (8.6%) and cocaine (3.9%).

It was also found that among weekend nighttime drivers, males were more likely (2.6%) to be intoxicated than were females (1.5%). The percentage of intoxicated drivers also increased from 0.2% during the daytime to 1.2% in the early nighttime to 4.8% during the late nighttime(between 1:00 a.m to 3:00 a.m.) See figure 2.

Figure 2
Figure 2: Percentage of Drivers with Illegal BACs by Time of Day (Fridays and Early Saturday Mornings)

Although drugged drivers outnumber drunk drivers 7.4 to one on weekend nights, and although drunken driving has dropped dramatically over time, we must both continue and expand efforts to reduce drunken driving. One effective approach is to establish DWI courts.


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Filed Under: Drinking and Driving