The challenge
Alcohol-involved offences such as drunk driving and domestic violence were harming public health and safety.
The case
South Dakota's 24/7 Sobriety Project requires people arrested for or convicted of alcohol-involved offences, such as drunk driving, to take breathalyser tests twice a day or wear a continuous alcohol-monitoring bracelet. Anyone who tests positive faces swift, certain and modest sanctions. Between 2005 and 2010, more than 17,000 residents took part, including over 10% of men aged 18 to 40 in some counties. RAND researchers compared counties that adopted the program with those that hadn't yet. Adoption was followed by a 12% reduction in repeat drunk-driving arrests and a 9% reduction in domestic violence arrests at county level. Evidence on traffic crashes was mixed.
Why it worked
Frequent testing with immediate, predictable consequences reduced problem drinking and its harms, a lesson for how community supervision is designed. The program was not randomised, so the results rest on comparing counties that adopted it at different times.
Sources
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