Michigan's Motorcycle Helmet Law Modification: An Observation Study

Motorcycle crashes are a significant public health burden and motorcycle helmet use has consistently been shown to reduce that burden. Jurisdictions that have universal helmet laws requiring use from all riders have consistently lower fatalities and less head trauma than jurisdictions that do not have such legislation. In 2012, Michigan modified its universal helmet legislation to require only motorcyclists under age 21 to wear helmets. The current study reports findings from a subsequent observational assessment of helmet use. There were 1355 observations of motorcyclists made from May-September 2014. Helmet use and type (e.g. full face, open face, half face, novelty helmet) and motorcycle class were observed on various roadway types at different times of the day and days of the week. Helmet use was more common among riders of sports motorcycles, on freeways and in the morning, and least common among riders of cruisers, on minor arterials, and in the afternoon. The observation data were used in conjunction with State crash records to estimate the helmet use rate statewide. The rate of helmet use across Michigan was estimated at 77.4% (CI: 74.1-80.6%) following adjustment for roadway type, motorcycle class and time of day. This compares to the rate identified in the state crash data of 74%. Findings highlight characteristics of motorcyclists who chose not to wear a helmet following the change of legislation. Understanding the motorcyclist and conditions in which helmets are not worn can be used to target safety interventions in the absence of universal helmet laws.