Drunk driving risk factors​

Alcohol concentration

Even at an Alcohol Content (AC) level as low as 0.04%, alcohol in your blood system affects driving ability and crash likelihood, according to Special Report 216, "Zero Alcohol" by the Transportation Research Board.

  • The probability of a crash begins to increase significantly at 0.05 AC and climbs rapidly after about 0.08%.
  • For drivers with AC's above 0.15% on weekend nights, the likelihood of being killed in a single-vehicle crash is approximately three times higher than it is for non-drinking drivers.


Alcohol-related crashes in Wisconsin are much more likely to involve men than women.

  • ​Among fatally injured male drivers in the year 2015, 31% of those tested had AC's of 0.08% or more and women tested for .08 or above were 15%. These numbers are taken from all of the fatalities that were tested. 
  • ​Men, ages 21-24, are the most likely drivers to be killed in a crash when their blood alcohol content is above 0.08.


Male drivers ages 21-40 make up the majority of fatally injured drivers with high AC's. This group has shown only a modest decline in the 1980s in the percentage of fatally injured drivers with high ACs.

In contrast, other age groups, particularly teenagers, show substantial declines. Drivers in the 16-20 year-old group showed the biggest improvement throughout the 1980s, due largely to the 21-year-old alcohol purchase laws.

Wisconsin Driver Age and Crash Involvement 2015
Age Total number
in crashes
Number who had been
drinking in crashes
14 and under690.0%00.0%
15 to 1919,0309.5%2424.7%
20 to 2424,77012.3%1,14122.3%
25 to 4466,77233.2%2,33245.5%
45 to 6452,52826.2%1,22323.9%
65 to 8417,0398.5%1683.3%
85 and up1,5200.8%40.1%
Totals 200,866 100.0% 5,121 100.0%