The one thing helmet laws seem to do that may be a public health risk, at least in cities with bike share systems, is suppress how many people ride. When you ca

The one thing helmet laws seem to do that may be a public health risk, at least in cities with bike share systems, is suppress how many people ride. When you cannot ride a bike without a helmet, a good chunk of people will opt to take a car or walk instead of using a bike share. To my knowledge, the number of cyclist collisions stays relatively constant with the number of cyclists: more cyclists mean around the same total number of collisions, which is fewer on a per trip basis. As a benefit, by acting as a natural barrier between deadly fast steel boxes and pedestrians, having a lot of cyclists also saves pedestrian lives.