California drivers have been sharing the roads with Uber and Lyft drivers for more than five years, and while the companies claim to be a scourge to drunk driving, some scientists are not convinced. Researchers have had varied results when studying the effects of ride-sharing services have had on the rates of drunk driving in an area.

According to Fortune, a 2015 study conducted by Uber and Mothers Against Drunk Driving found that California counties that were serviced by Uber had 60 fewer car crashes each month by drivers under the age of 30 since July 2012. However, independent studies have not always agreed with these findings. A study published in July 2016 found that after comparing traffic data from before and after Uber and its competitors arrived in over 100 major metro areas across the U.S., there was no discernible difference in alcohol-related accidents or accident rates taken as a whole. This study provides a sharp contrast to the claims Uber has made on its contributions to the safety of the communities it services. 

Yet another study reported in the New York Times found that ride-sharing services did correlate with a decrease in alcohol-related accidents. The researchers from this independent study found that the boroughs of New York City, excluding Staten Island, saw a dip between 25 and 35 percent of alcohol-related car crashes since ridesharing came to the area in 2011 when compared to communities without these services. However, while Uber may feel comfortable claiming credit for these successes, scientists do not think that the correlation is enough to be considered conclusive evidence that this reduction is due entirely to ride-sharing services.