Effect of Increased Local Enforcement Activities on Community Alcohol Problems

California’s Strategic Planning Framework/State Incentive Grant from the Center for Substance Abuse Prevention (SAMHSA) created an opportunity to test the effectiveness of enhanced enforcement of standard alcohol control measures within a randomized control trial (RCT). Twelve pairs of cities with populations between 50,000 and 450,000 were selected at random and roughly matched before one from each pair was chosen at random as an intervention community.

The intervention aimed at reducing excessive and underage drinking among 12 to 25 year-olds, and included enhanced enforcement of laws against selling alcohol to minors, DUI enforcement, responsible beverage service, and party patrols to reduce nuisance parties or those with minors in possession of alcohol. The intervention started in January 2013. Data sources included Statewide Integrated Traffic Records System (SWITRS) for 2010-2015 counts of MVCs, alcohol-related MVCs, and alcohol-injury-related MVCs and Monthly Arrest and Citation Register (MACR) for 2010-2014 counts of arrests for violent felonies and sex offense felonies. Annual population counts were obtained from the California Department of Finance intercensal estimates and used to calculate arrest rates per 100,000 population. Mixed modeling was used to generate ratios of risk ratios (RRR) to estimate the effect of increased enforcement activities on alcohol problems.

From 2010-2015 there were 140,430 MVCs. 9.6% were alcohol-related and 3.5% were alcohol-injury-related. From 2010-2014 there were 1,984 sex offense felony arrests (17.3 per 100,000) and 29,635 violent felony arrests (258.0 per 100,000). There was no reduction in the proportion of alcohol-related MVCs or alcohol-injury-related MVCs after increased enforcement activities [RRR(95%CI)=0.98 (0.82, 1.17) and 0.92 (0.74, 1.15), respectively]. Similarly, there was no reduction in arrest rates for either violent felonies or sex offense felonies after increased enforcement activities.

Preliminary results show there was no reduction in alcohol problems after increased enforcement activities. One possible reason is the data were not collected for the purposes of this study. For example, MACR data available only included annual (not monthly) counts of arrests, limiting power to detect any potential effect of increased enforcement activities. Another potential reason is that while twelve cities were designated as intervention cities, not all cities engaged in all prescribed enforcement activities. This variation in enforcement could attenuate potential effects of increased enforcement activities on problems. Additional studies should be conducted to determine whether other strategies of increased enforcement of alcohol control measures may reduce community alcohol-related problems.