Traffic collisions are a major cause of death and serious injury in America, especially at holidays. The number of fatalities has hovered around 40,000 a year since about 1938 even though the population has tripled and the number of miles driven is over10 times as high. The flat curve is due to better cars, better roads, better licensing, better emergency response, and better medical intervention. Statistics on injuries are harder to analyze, death is binary, you are either dead or not. There are a lot of injured but not dead. Ranging from refused treatment to vegetative state. The biggest uncontrolled variable is driving-while-impaired.
Impairment is harder to define than we would like. The most reliable current measure is the battery of field sobriety tests that a qualified officer can administer at or near the time of incident, arrest or crash. Unfortunately, the defense lawyers have a battery of countermeasure that make it hard to get a conviction for driving while impaired based on a field test done by a subjective human; what the courts prefer is a scientific test that results in a single number from a laboratory. That which in politics is referred to sarcastically as a litmus test.
Depending on the jurisdiction, a blood alcohol content (BAC) above a certain number within a certain time is prima facia evidence of impairment. Ignoring the fact that BAC can change significantly in two hours, up or down. Ignoring the fact that the relationship between BAC and impairment varies between individuals. Ignoring the fact that the suspect can be impaired for a hundred other reasons that have nothing to do with BAC. Many of the drugs that cause impairment have no quantitative test available so even if detected there is no correlation. A person could be impaired due to legal levels of multiple substances. One toke, one shot, one snort, one oxycodone, and exposure to paint thinner. Many environmental factors, things not are not even drugs can cause impairment. Some people are simply incompetent to drive due to personal condition such as sickness, fatigue, senility, injury, or diminished eyesight. The legal system prefers a litmus test.
We have to ask ourselves “What is the goal? Fewer injuries or easier convictions.”
Just as field sobriety tests have met defense resistance and clever, frankly unscrupulous tactics, so has BAC. The response from the safety community is typical politics. If what you are doing is not having the desired effect, do it more. Lower the BAC threshold, even though most who crash are way over; expand the number of laboratories, make the law more inclusive, stricter penalties and short cut due process. Build BAC detection into every new car, as if drunks can’t buy a used car. Install alcohol breath detection in every car so no one can even drive a drunk friend home. Ignore impairment for which there is no quantitative test. De-emphasize or ridicule field sobriety testing for actual impairment.
There is another alternative that the BAC community resists even discussing. Automated impairment tests. Airline pilots take a qualification test series twice a year. That requires an expensive simulator. There are however tests that can be built into a hand-held device. Some self-tests are already available for a smart phone and the plethora of video games offers hundreds of possibilities. A simulator could be built into a dedicated car for use at roadside sobriety checkpoints.
Ultimately physical impairment testing could be built into cars to detect signs of impairment, like closed eyes, nodding, inappropriate reaction or movement. We can do better than a lab test two hours after the crash.
Ken Obenski is a forensic engineer, now safety and freedom advocate in South Kona. He writes a biweekly column for West Hawaii Today. Send feedback to obenskik@gmail.com.