The data on bike helmets have changed. Laws are starting to change too.

The Board of Health in King County, Washington voted last week "to repeal its decades-old mandatory helmet law for bicycle riders," reports David Kroman for the Seattle Times. The decision to rescind the 1993 law came after data revealed that the law was enforced selectively, disproportionately targeting people of color and people experiencing homelessness.
As explained by Kroman, in 1993, evidence suggested that mandatory helmet laws would increase helmet use and reduce the severity of injuries. Kroman provides this summary of more recent research:
But recent data connecting helmet laws to their use and improved outcomes for cyclists is less clear. In Seattle, helmet use among riders of private bikes is as high as 91%, according to one study. Meanwhile, in Portland, which does not have an all-ages helmet law, one study found use is similarly high. A study in King County could not find any discernible impact on hospitalization rates following the law’s expansion into Seattle in 2003, although severity of injuries did decrease around the same time.
A separate article by Bicycle Retailer digs into the research behind the decision, including a study by Ethan Campbell, a PhD candidate at the University of Washington. A December 2020 article by Kroman, writing for Crosscut at the time, revealed data about the use of mandatory helmet laws to cite people experiencing homelessness.
The decision to drop the county's mandatory helmet laws to disparate impacts also made the New York Times, in an article by Sophie Kasakove.
FULL STORY: King County repeals mandatory bicycle helmet law

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