Smartphones, Online Music Streaming, and Traffic Fatalities

Modern smartphones present new threats to road safety beyond talking and texting, but the real-world effects are difficult to study. One way to causally assess the impact of smartphones on road safety is to identify arbitrarily timed events during which smartphone-related distraction may exogenously increase – i.e., a situation that relies not on plausibly random variation in who uses smartphones while driving, but when smartphones are used. We investigated the impact of smartphones on road safety by examining traffic fatalities on days when smartphone use likely surges: the release of major music albums. Using event study analysis, we show that music streaming – an indicator for smartphone use, where streaming most often occurs – sharply increases, by nearly 40%, on dates of major music album releases, while U.S. traffic fatalities increase by nearly 15% on those same days. Mobile device use while driving is a known safety issue, but today’s smartphones present new and greater opportunities for driver distraction. Our study indicates how features of these phones may have important impacts on distracted driving and traffic fatalities.