In 2015, more than 32,000 persons were killed in the United States as a result of motor vehicle crashes; 10,265 of these deaths involved an alcohol-impaired driver (NHTSA 2016). One solution to help reduce alcohol-impaired driving is the use of safe ride programs. These programs provide impaired drivers with alternative transportation such as taxi services and public transportation options to get home (Sarkar et al. 2005), and include both for-profit and non-profit safe ride programs. Many for-profit safe ride programs such as Uber and Lyft are similar to city taxis yet offer a lower fare and the increased convenience of hailing a cab through a mobile application. As a result of the increased use of both for-profit and non-profit safe rides, researchers have investigated the effect that safe ride programs have had on the number of alcohol-impaired traffic-related incidents, such as arrests, crashes, and fatalities that occur annually. Results from a variety of studies have suggested that the increased use of safe rides has led to a decrease in the number of alcohol-impaired driving vehicle crashes (Dills and Mulholland 2016; Greenwood and Wattal 2015; Huseth 2012). These findings have led some researchers to conclude that safe rides are an effective method of decreasing impaired driving arrests, crashes, and fatalities. The studies included in this literature review were identified through a systematic search of online catalogues of relevant libraries. Approximately 40 articles and studies were reviewed and included in this literature review after searching the online catalogues and libraries using a variety of key terms. These key terms included impaired driving, safe rides, safe ride programs, ride-sourcing, ridesharing, transportation network companies, Uber, and Lyft. After an initial search using these terms, the terms were then coupled with additional key terms, such as traffic, DUI/DWI, alcohol, and law enforcement. The review includes findings from studies that examined the effect of safe ride programs on alcohol-impaired driving arrests, crashes, and fatalities. When investigating the effect of both for-profit and non-profit safe ride programs on alcohol-impaired driving arrests, seven studies suggested a relationship between safe rides and a resulting reduction in impaired driving arrests. Using data from the Federal Bureau of Investigation Uniform Crime Reports (UCR), a 2016 study indicated that a one-time 33% decrease in impaired driving arrests occurred following the entry of Uber in various counties across the United States (Dills and Mulholland 2016). A study investigating the effect of a university safe ride program on alcohol-impaired driving arrests determined based on city police data that there was a 1.75% decrease in impaired driving arrests after the implementation of the program (Elam et al. 2006). The decrease of alcohol-impaired driving crashes after the entry of Uber has been dubbed the “Uber Effect.” To investigate the impact of the Uber Effect in California, Mothers Against Drunk Driving (MADD) conducted a study examining the number of monthly alcohol-related crashes before and after the entry of Uber in California. Results of the study indicated that an estimated 1,800 alcohol-related crashes had been prevented in California since the entry of UberX in July 2012 (MADD 2015). Four studies examining the impact of safe ride programs on alcohol-impaired driving fatalities were included in this review. Of the four studies, three reported that safe ride programs have a causal effect leading to a reduction of alcohol-impaired driving fatalities, but the study periods were relatively short, especially the post-implementation period. In contrast, a 2016 study by Brazil and Kirk showed that Uber had little to no effect on traffic fatalities. The study examined the relationship between the deployment of Uber and subsequent alcohol-related traffic fatalities in the 100 largest metropolitan areas in the United States from 2005 to 2014 (Brazil and Kirk 2016). Three categories of traffic fatalities were considered in this study: total, impaired driving, and weekend/holiday-specific. While results indicated that counties experienced an increase in the total number of traffic fatalities during the months Uber was present, the number of weekend/holiday-specific fatalities decreased (Brazil and Kirk 2016). Researchers attributed this to the fact that Uber represents a relativity small portion of the transportation market within the United States. As such, the lack of an effect was not considered surprising by authors in light of the large number of annual alcohol-related traffic fatalities; approximately 10,000 per year (Brazil and Kirk 2016). While many studies included in this review suggest that safe ride programs have a positive impact on the reduction of alcohol-impaired driving arrests, crashes, and fatalities, it cannot be explicitly concluded that safe ride programs reduce impaired driving crashes and fatalities. To date, the evidence available supports only a correlational relationship rather than a causal one. As such, the available evidence suggests safe ride programs are a promising method to decrease incidents of alcohol-impaired driving, but further exploration of these effects is necessary in order to conclude these programs are definitively effective. (Author/publisher)
Samenvatting