Study finds Utah's .05% BAC law linked to drop in alcohol-related crashes

SALT LAKE CITY — Utah's first-in-the-nation decision to lower its legal blood alcohol concentration limit to .05% appears to be paying off, according to a new study that found an overall decline in alcohol-related crashes since the law took effect.

Researchers with the Insurance Institute for Highway Safety analyzed crash data beginning in 2018, when Utah lowered its BAC threshold from .08 to .05. Their findings show a nearly 9% reduction in alcohol-related crashes.

"Utah is unique in the United States. It's the only state that has a limit at .05," said Joe Young, media relations director for the institute. "Researchers have been very interested to understand what the potential benefits of that change have been."

Utah remains the only state in the nation with a .05 BAC limit, though Young said many other countries use the same threshold. The National Transportation Safety Board has also encouraged states to consider lowering their limits.

Researchers say studies have shown driving abilities can be impaired even when a person's BAC is below the traditional .08% threshold.

"You see reduction in the ability to maintain your lane, for example, slowed reaction time," Young said.

The study found alcohol-related crashes initially declined after the law was implemented, before increasing during the COVID-19 pandemic. Since then, state officials say crash numbers have returned to a downward trend.

"Here in Utah, we have seen a decrease since 2023, kind of getting back to normal to where we were pre-law change," said Jason Mettmann, communications director with the Utah Highway Safety Office.

While crash numbers have fallen, he said DUI arrests have increased.

"On average, the BAC on a DUI arrest is .15. That's three times the legal limit," he said.

He said the trend suggests the most significant threat on Utah roadways comes from drivers with extremely high levels of impairment.

Mettmann also credited increased enforcement efforts and tougher penalties for helping reduce DUI crashes. One recent measure, HB437, requires a red banner that states "No Alcohol sale" to appear on the driver's licenses of people convicted of extreme DUI offenses.

"That's just another tool in our toolbox that if we have an extreme DUI offender, that they're not able to go out and make that purchase at a liquor store or, at an alcohol retailer," he said.

Researchers acknowledged Utah's unique culture surrounding alcohol could influence the findings. Still, they hope the results encourage other states to examine whether lower BAC limits could improve roadway safety.

"We certainly would hope that other states are paying attention and seeing the benefits that we're seeing in Utah and that have been seen in other parts of the world as well that have made this change," Young said.