One thing I can tell you about bicycle safety--I wear an eyeglasses-mounted rear view mirror, and it has saved my can lots of times from cars moving up behind me. I always have a rear-view mirror along.

A helmet helps you avoid injury if you crash, while a rear-view mirror helps you avoid crashing in the first place. So you tell me, which is more important?

All the people I see wearing helmets, and yet it is still very rare to see any that have rear-view mirrors of any kind. They'd be safer just easily being aware of what traffic was behind them all the time. A rear-view-mirror law would make much more sense to me than a helmet law.
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