This is a great video that covers all the relevant issues regarding a very heated topic, should you wear a bike helmet while cycling? And more to the point, should everyone be forced to wear one?
I wear a helmet every single time I get on my bike. But, I also take objection to efforts to make wearing a helmet compulsory, because when it comes to genuine efforts to make cycling safer they are a red herring. “We made everyone wear a helmet! Now we don’t have to work on making infrastructure safe for cyclists, enforce traffic laws, or raise driver awareness!”
In short, mandatory helmet and high-visibility clothing laws are attempts to shift the burden of safety away from the motorist and make it the cyclists responsibility to armor themselves.