Restricting Hours of Sale in Diadema, Brazil: Effects on Homicides and Assaults on Women Sergio M. Duailibi*, Ronaldo Laranjeira*, William Ponicki, Joel W. Grube, John H. Lacey Prevention Research Center, Berkeley, California, USA INTRODUCTION This study examined the impact on rates of homicides and assaults on women of a city ordinance restricting hours of sale of alcoholic beverages in Diadema, Brazil. Diadema is a low-income city of over 357,000 people located south of São Paulo. The community had very high rates of homicides, assaults, vehicle crashes, and gang violence. Many of these incidents occurred between 9:00 PM and 6:00 AM. In response, the municipal government passed an ordinance effective July, 2002 that prohibited on-premise alcohol sales between the hours of 11:00 PM and 6:00 AM. Previously there were no sales-hour restrictions and most establishments remained open 24 hours. The ordinance mandated progressive penalties: (a) a warning for first offense, (b) a fine for a second offense, (c) fine and license suspension for a third offense, and (d) license cancellation for a fourth offense. Teams of municipal guards and representatives of other city agencies were assigned on a random basis to enforce the ordinance. Local news, radio and educational brochures distributed to the community were used to increase awareness of the new ordinance. A toll-free number was provided to allow the public to report offenders. Surveys indicated a high level of community receptivity and participation with more than 90% approval after 1 year. METHOD OLS regression time series analyses were used to investigate the effects of the new ordinance on rates of homicide and assaults on women. A dummy variable was used to represent the proportional impact of the closing- hours ordinance (0 prior to implementation, 1 after implementation). Various controls for underlying time trends were tested, including linear and quadratic trends. Dummy variables were included in the homicide analyses to control for unrelated increases in enforcement in greater São Paulo in January and July 2000. MEASURES Homicides Logged monthly homicide rates per 1000 residents, January 1995-July 2004. Assaults on Women Logged monthly rates of assaults on women per 1000 residents, July 2000- July 2004. RESULTS Homicide and Assault Rates Monthly counts for homicides ranged from 6 to 41. There were an average of 301.3 homicides per year before the intervention and 169.6 per year afterward. Monthly counts for assaults on women ranged from 13 to 72. They averaged 570.8 per year before the intervention and 351.7 per year afterward. Figure 1 shows the monthly homicide rates from 1995-2004. Table 1 shows the results of the regression analyses of these data. All analyses indicated that implementation of sales hours restrictions were associated with a significant reduction in homicide rates. The preferred model, including the linear trend for time, the effects of earlier enforcement in January 2000, and the implementation of the closing hours ordinance, estimated that the sales hours restrictions reduced homicide rates by 46%. These findings were robust to model specification and to the inclusion of controls for the earlier (2000) increases in enforcement. Assaults on Women Figure 2 shows the monthly rates for assaults on women from 2000-2004. Table 2 shows the results of the regression analyses on these data. The analyses indicate that implementation of sales hours restrictions was associated with a large (26%), but statistically nonsignificant reduction in assaults on women once underlying time trends were accounted for in the models. CONCLUSION The implementation of more restrictive sales hours was related to a significant reduction in homicides rates in Diadema, Brazil. Overall, it is estimated that restricting sales hours saved 273 lives in the 24 months following implementation (Table 3). An estimated 224 assaults on women were prevented, although the 95% confidence interval for this estimate was large (-66 – 514) and the effect was not statistically significant. The lack of effects on assaults on women may be due, in part, to the relatively short time series and the high variability of the data. Although alcohol availability theory predicts decreases in consumption and concomitant problems following increased restrictions on hours of sales, previous research has been inconclusive. In some studies, changes in hours of sale have been associated with changes in problems, including assaults (Chikritzhs & Stockwell, 2002), fatal traffic crashes (Smith 1988a), and intoxication (Voas, Lange, & Johnson, 2002). Other studies have found no effects of changes in sales hours (Bruce, 1980; McLaughlin & Harrison-Stewart, 1992; Smith, 1988b). The effects of restrictions on hours of sale may be greatest when they represent a substantial environmental change as was the case in the present situation. Relatively minor or temporary changes may have no or minimal effect. Effective enforcement is probably a key element. REFERENCES Bruce, D. (1980). Changes in Scottish drinking habits and behaviour following the extension of permitted evening opening hours. Health Bulletin, 38, 133-137. Chikritzhs, T. & Stockwell, T. (2002). The impact of later trading hours for Australian public houses (hotels) on levels of violence. Journal of Studies on Alcohol, 63, 591-599. McLaughlin, K. L & Harrison-Stewart, A. J. (1992). Effect of a temporary period of relaxed licensing laws on the alcohol consumption of young male drinkers. International Journal of the Addictions, 27, 409-423. Smith, D. I. (1988a). Effect of casualty traffic accidents of the introduction of 10 p.m. Monday to Saturday hotel closing in Victoria. Australian Drug and Alcohol Review, 7, 163-166. Smith, D. I. (1988b). Extended alcohol trading hours during the 1982 Brisbane Commonwealth Games and traffic accidents. Australian Drug and Alcohol Review, 7, 363-367. Voas, R. B., Lange, J. E., Johnson, M. B. (2002). Reducing high-risk drinking by young Americans south of the border: The impact of a partial ban on sales of alcohol. Journal of Studies on Alcohol, 63, 286-292. This research and preparation of this poster were supported by NIAAA grant #AA06282 *Department of Psychiatry, Federal University of São Paulo, Brazil