Could further lowering of drunk driving limits save thousands of lives in the US?

The question in the title of this post is prompted by this new New York Times piece headlined “How Much Alcohol Is Too Much for a Driver?  Experts argue the U.S. drunk-driving limit is too high.”  I recoemmend the piece (and its many links) in full, and here are excerpts:

In late 2018, Utah lowered its drunk-driving limit from a B.A.C. (blood-alcohol content) of .08 to .05.  A year after the law was implemented, the National Highway Traffic Safety Administration found that fatal car crashes in the state had dropped by nearly 20 percent.

“Believe me, I never thought we would see a significant effect in Utah,” said James Fell, a principal research scientist who studies traffic safety at the independent research organization NORC, at the University of Chicago.  The state had one of the lowest impaired driving rates in the United States to begin with, he added.

Utah is currently the only state in the country with a .05 drunk-driving limit; everywhere else, the limit remains .08. But internationally, Utah is far from alone. Australia, France, Thailand and about 50 other countries have a B.A.C. limit of .05, and in more than 30 other countries, the limit is even lower.

With U.S. drunk-driving deaths rising in recent years (about 33 percent between 2019 and 2022, according to the most recent data), several other states — including New York, Washington, Hawaii and Connecticut — are now considering similar legislation to lower the legal driving limit.  “We’re losing, on the highways these days, more than 13,000 people a year,” said Thomas Chapman, a member of the National Transportation Safety Board. “I mean, it’s just an astonishing number.” In 2022, drunk-driving accidents accounted for 32 percent of all traffic fatalities.

The current national drunk-driving limit wasn’t established until 2000, when Congress passed a bill that required all states to set their B.A.C. limit at .08 in order to continue receiving federal highway funds.  Before then, some states used .08, while others used .10.  Even at that time, some researchers and advocates thought the limit should be as low as .05….

Experts say that the science strongly supports a lower B.A.C. limit.  Multiple studies testing people’s cognitive faculties when drinking have found that both sustained attention and multitasking are already impaired at .05.  People become drowsy at even lower levels of intoxication.  And on driving simulators used in a lab setting, people perform worse with any amount of alcohol in their system.

Looking at how these impairments affect people’s driving in the real world, one study reported that people with a B.A.C. of .05 had a 38 percent higher risk of getting into a car crash than those with no alcohol in their system; at .08, the risk rose to 169 percent.  And an analysis Mr. Fell conducted in 2017 estimated that lowering the legal limit nationally to .05 could reduce alcohol-related fatal crashes by 11 percent, saving nearly 1,800 lives per year….

According to the experts interviewed for this article, one of the main opponents is the hospitality industry, which argues that a B.A.C. limit of .05 would hurt restaurants and bars…. In Utah, there was little evidence that this happened. The National Highway Traffic Safety Administration report found that alcohol sales in the state continued on a steady upward trajectory from 2012 to 2020 and were not disrupted by the passage or implementation of the law. That study provided “important” evidence that a lower B.A.C. limit did not have a “negative impact on alcohol sales or tax revenues or tourism,” Mr. Chapman said.  Rather than drinking less, the report stated, people were more likely to find an alternate way home.

In approximately half of all fatal crashes involving alcohol, drivers have a B.A.C. of .15 or higher, so a lower limit may not deter the worst offenders any more than the current laws do.  However, it could influence those who are mindful of the limit but might not recognize when they are impaired.

Long time readers may recall that I have long supported lowering of BAC levels in drunk driving laws, in addition to a range of reasonable efforts (including sentencing sanctions like ignition locks), that have been consistently shown to reduce highway fatalities associated with drinking and driving.  (Here is post on this front from back in 2013 with lots of additional links.)  Even before our smart phone era, I never have felt it was too much to ask drinkers to find a safe way home other than driving.  And with Uber and Lyft now providing such an available means for always accessing a safe ride home, I hope many states will look to save lives and reduce other avoidable harms by lowering their drunk driving limits.