Utah’s decision to lower the legal blood alcohol concentration (BAC) limit for drivers from 0.08% to 0.05% has resulted in a nearly 9% decline in alcohol-related crashes over four years, according to a new study by the Insurance Institute for Highway Safety (IIHS). This makes Utah the only U.S. State with a 0.05% BAC limit, a standard backed by scientific research showing a sharp rise in crash risk starting at that level.
The stricter BAC limit sends a clear message that even a small amount of alcohol impairs driving ability, reinforcing the idea that buzzed driving is drunk driving. The new findings come after Utah’s law took effect in December 2018 and follow earlier research showing a drop in fatal crashes in the first year.
How Utah’s BAC law changed crash rates
Researchers analyzed four years of crash data, including cases where alcohol involvement was confirmed after the crash or where drivers refused BAC tests. They also compared Utah’s results with neighboring states Arizona, Idaho, and Colorado, which did not lower their BAC limits.
Despite Utah’s already low alcohol-involved crash rates—partly due to cultural factors—the study found a significant drop in crashes involving alcohol after the law’s implementation. Relative to previous years, alcohol-related crashes fell nearly 9% following the law’s start, while injury crashes involving alcohol dropped 12%.
The study accounted for complicating factors like the early publicity of the law and the COVID-19 pandemic, which briefly increased alcohol-related crashes by 46% during lockdowns but did not erase the overall positive impact of the lower BAC limit.
What it means for you
The Utah study suggests that lowering the legal BAC limit can reduce alcohol-related crashes, even in states with relatively low baseline rates. For drivers, this means stricter enforcement and a smaller margin for safe alcohol consumption before driving.
States considering similar laws may see even larger benefits, as Utah’s unique alcohol culture might have limited the potential impact. The findings reinforce the importance of sober driving and could influence future state policies to improve road safety.
Next steps for states and drivers
With more than 10,000 annual U.S. Deaths linked to alcohol-related crashes, IIHS President David Harkey urges other states to consider adopting a 0.05% BAC limit. While Utah remains the only state with this law, the evidence shows it can be an effective tool to save lives.
Drivers should be aware that even small amounts of alcohol can impair driving and increase crash risk. Staying below the 0.05% BAC limit or avoiding alcohol before driving is the safest choice.
