Extended evaluation of the effects of Utah’s 0.05% BAC per se law on crashes: an update with additional years and regional contrasts
Tippetts, A. Scott / Eichelberger, Angela H.
Insurance Institute for Highway Safety
October 2026
Abstract
The National Transportation Safety Board has recommended that states lower the per se blood alcohol concentration (BAC) limit from 0.08% to 0.05% in a national effort to reduce alcohol-impaired driving. Most industrialized nations have established a 0.05% or lower BAC limit for driving. In December 2018, Utah became the first U.S. state to establish a 0.05% limit, and early research showed some evidence that the law reduced alcohol-involved crashes in its first full year of implementation. Examining 4 full years of the law’s impact, this study shows it had continued benefit, both independently and in contrast to neighboring states, despite the unusual changes in drinking-driving behavior resulting from COVID-19 pandemic disruptions. The uniqueness of the alcohol environment in Utah and the confounding effects of the pandemic prevent us from determining the size of the effect.
The National Transportation Safety Board has recommended that states lower the per se blood alcohol concentration (BAC) limit from 0.08% to 0.05% in a national effort to reduce alcohol-impaired driving. Most industrialized nations have established a 0.05% or lower BAC limit for driving. In December 2018, Utah became the first U.S. state to establish a 0.05% limit, and early research showed some evidence that the law reduced alcohol-involved crashes in its first full year of implementation. Examining 4 full years of the law’s impact, this study shows it had continued benefit, both independently and in contrast to neighboring states, despite the unusual changes in drinking-driving behavior resulting from COVID-19 pandemic disruptions. The uniqueness of the alcohol environment in Utah and the confounding effects of the pandemic prevent us from determining the size of the effect.
Abstract
The National Transportation Safety Board has recommended that states lower the per se blood alcohol concentration (BAC) limit from 0.08% to 0.05% in a national effort to reduce alcohol-impaired driving. Most industrialized nations have established a 0.05% or lower BAC limit for driving. In December 2018, Utah became the first U.S. state to establish a 0.05% limit, and early research showed some evidence that the law reduced alcohol-involved crashes in its first full year of implementation. Examining 4 full years of the law’s impact, this study shows it had continued benefit, both independently and in contrast to neighboring states, despite the unusual changes in drinking-driving behavior resulting from COVID-19 pandemic disruptions. The uniqueness of the alcohol environment in Utah and the confounding effects of the pandemic prevent us from determining the size of the effect.Alcohol and drugs: Drinking and driving, ID: 2382