Utah's 0.05% blood alcohol limit linked to reduction in crashes

A study by the Insurance Institute for Highway Safety (IIHS) indicates that Utah’s decision to lower its legal blood alcohol concentration (BAC) threshold has led to a long-term reduction in alcohol-related crashes. Utah became the first and remains the only U.S. state to lower its BAC limit from 0.08% to 0.05% in December 2018.

Researchers found that in the four years following the implementation of the stricter limit, alcohol-involved crashes in Utah fell by nearly 9%. Specifically, the percentage of injury crashes involving alcohol declined by 12%. During the same period, alcohol-involvement rates in comparison states, including Arizona, Colorado, and Idaho, increased.

The study also accounted for the impact of the COVID-19 pandemic, noting that while alcohol-involved crashes in Utah rose briefly in early 2020, the overall downward trend persisted. The National Transportation Safety Board has previously recommended that states lower their limits to 0.05%, citing significant impairments to depth perception and reaction time at that level.