Drinking drivers range from the young binge drinker to the middle-aged tippler to the hard-core alcoholic, notes the Traffic Injury Research Foundation in a new report, Understanding Drunk Driving. Because drinking drivers are not all the same, the tactics used to reach them must also vary, says the report.

TIRF has produced Understanding Drunk Driving as one of a series of reports under the authorship of the Working Group on DWI System Improvements. The report notes that is important that drunk driving issues be understood clearly so agencies do not work at cross-purposes from one another or deliver incorrect messages. TIRF divides drinking drivers into five groups:

Legal drinking drivers

Most people who drink and drive do it rarely and when they do, their blood alcohol concentrations tend to be under the legal limit. Their risk of being involved in a serious crash is relatively low, compared to the average non-drinking driver, though it varies depending on age and gender. Still, legal BACs of .03% are linked to a two- to three-fold increase in risk, and BACs of .05% to a 6-17 times greater risk of a serious crash. And while this group is at lower risk of causing a serious crash than those with higher BACs, because there are so many of them on the roads, they pose a risk and need to be deterred. TIRF says there is evidence these people are more amenable to traditional interventions such as high visibility spot checks, leading to fear of arrest and thus general deterrence.

First offenders

These people are a large majority of the drunk driving problem, TIRF says. Research suggests that once drunk drivers are arrested for the first time, two-thirds will be deterred by their experience with the criminal justice system and will not be arrested again. One-third will reoffend, likely some of whom have drinking problems. The report recommends screening and assessment of first offenders to identify those at high risk, helping to determine whether they need treatment or greater supervision.

High-risk offenders

An estimated 30% of offenders become repeat offenders who drink and drive regularly, often at high BACs. Many are alcoholics and their tendency to drink excessively puts them at high risk of causing a serious crash. For example, drivers with a BAC of .15% are 150 times more likely to have a fatal crash than the average non-drinking driver and at .20%, 460 times more likely. This “particularly challenging group of offenders” needs strategies that combine punishment, surveillance and treatment, TIRF suggests, along with strategies to reinforce positive behaviour to encourage change.

Young drinking drivers

Young drinking drivers are at high risk because of their inexperience both in driving and in drinking. For example, when sober, 16-19-year-olds have a fatal crash rate nine times as high as drivers 45-54. And as inexperienced drinkers, they are more impaired at even low levels of alcohol. Plus young drinkers are often binge drinkers. Fortunately, TIRF says, young drivers are the least likely of any age group to drink and drive. But for those who do, they are at much greater risk of collision than any other age group.

The report says young impaired drivers must be targeted because they are amenable to behaviour change and we don’t want them becoming the high-risk repeat drunk drivers of tomorrow.

Female drunk drivers

There is evidence that, while men still account for most impaired driving arrests, their rates are falling slightly while the number of women drinking and driving is on the increase. Most drunk driving countermeasures have been developed to target male offenders, the report notes. Measures targeting women specifically ought to be developed.

The report goes on to discuss strategies to make the justice system dealing with impaired driving most effective and efficient.

Visit http://www.tirf.ca to read Understanding Drunk Driving and other reports on driving issues.