The problem I see here is that any law to help someone to feel safe is an infringement on someone elses's freedom. We have laws against murder for example, that obviously infringe people's freedom, but we way it up and decide it's definitely better to have such laws. The "unrestricted free speech" arguement tends to have so many exceptions "calling fire" etc. that I feel you can't really argue against this.
Disclaimer: Brit, supporter of reasonable speech