Study: Lowering Legal Blood Alcohol Level To 0.05 Could Save Lives

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(Kenzo Tribouillard/AFP/Getty Images)
(Kenzo Tribouillard/AFP/Getty Images)

The current legal limit for blood alcohol concentration, or BAC, when driving is 0.08. But a new study from the National Academies of Sciences, Engineering and Medicine says it should be lower — 0.05.

Supporters say it's about time, and the National Transportation Safety Board recommended that change in 2013. Critics say it's too tough.

Dr. Tim Naimi, one of the study's authors, says its findings come amid misconceptions about drunken driving in the U.S. today.

"Unfortunately, the number of alcohol-related crash deaths in the U.S. has plateaued for some time," Naimi tells Here & Now's Robin Young. "I think a lot of people thought, 'Oh, drunk driving is sort of a thing of the past.' But it's not the case."

Interview Highlights

On how the 0.05 recommendation was reached

"There's a number of things that we evaluated, and one of them as you mentioned was reducing the BAC limits from 0.08 to 0.05. Most people in the developed world live with 0.05 laws or lower. Most of the evidence is pretty firm that 0.05 laws save lives, and probably could reduce the number of deaths each year by about 10 percent."

On how many drinks it would take for a person's blood alcohol concentration to approach 0.05

"It varies a lot from person to person. It depends on the size of the drink, it depends how fast that the drink is consumed, it depends on your sex and it depends on your body mass. And I would also say that regardless of whatever the legal limit is, the best advice is, it's good not to drink and drive.

"Even for a woman who's only 100 pounds, for example, who drinks a standard drink very quickly, say within 15 or 20 minutes, usually their BAC will top out around 0.04. For more typical sized woman, it would take two drinks to reach 0.05, and for a typical size man, it would take three drinks to reach 0.05 — and again, I'm just talking in generalities. I think it's good to know that for most people, if they go and they decide that they are comfortable drinking something and then driving, and they feel certain that they're not impaired, that it's pretty unlikely that somebody is gonna have a beer or a glass of wine and is going to end up arrested for DUI."

"Most of the evidence is pretty firm that 0.05 laws save lives, and probably could reduce the number of deaths each year by about 10 percent."

Dr. Tim Naimi

On people possibly being impaired after having two or three drinks during a night out

"Again, I'm sympathetic to people who go out and who drink. But the point is it's incumbent on all of us since it's not only their own safety, but remember that about almost half of all people who die in impaired driving crashes are actually not the drinking driver. Again, in general, it's incumbent on all of us that if we are drinking, that we either not drive or that we make sure that we're not putting ourselves or perhaps more importantly other people at risk. The risk of a crash starts to go up at about 0.02, and by the time you're at 0.05, your risk of a crash is increased several fold."

On the report's other recommendations

"The first thing I think we did that's important is recognize that when it comes to impaired driving, it's both a drinking issue and a driving issue, and you've been talking about, 'Well, what if you have two or three drinks?' Well the fact is that most people who drink and drive have had eight or nine or 10 drinks. So that's something we can definitely work on. Some of the ways to do that are by things like raising alcohol taxes, by preventing people who sell alcohol selling to people who are already intoxicated. That's against the law, but those laws are very rarely enforced.

"And then on the driving side, we absolutely agree that 0.05 is just one of a number of recommendations we had. Now, a lot of people are interested in new technologies. One of them is something called ignition interlocks, so ignition interlocks are devices for people who have DUI offenses, and it basically makes them blow into a sort of a breathalyzer before they can start their car. A number of states now have interlock laws, but our key recommendation is that people should be required to have interlocks even for a first DUI offense. Usually, people are only even stopped for DUI once every 100 or 200 times that they do it. In other words, it's actually unfortunately pretty tough to get caught. So if you wait until somebody has multiple convictions for DUI, then you're gonna be missing things. And even as it is, more than half of people who die in drunk-driving crashes, the culpable driver has never been convicted of a DUI charge. And then the other thing is, we don't wanna just sort of focus on the interlocks, we also want people who have drinking problems to be able to get help and get access to treatment."

This article was originally published on January 30, 2018.

This segment aired on January 30, 2018.



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