There were hate speech laws in Germany in the 1930s. Several Nazi leaders were prosecuted and some spent time in jail. Though some might argue that the German laws were not strong enough, creating a more powerful law simply runs the risk of capturing more speech that should not be censored. At the same time, there is no certainty that such laws will work. If history is to be our guide, time and time again we see that passions and ideas cannot be snuffed out by prosecution.
Ideas are singularly resistant to, and flourish in spite of, official persecution and legislation.
Perhaps the most poignant lesson to be learned from the German experience is that there is increased danger whenever a citizenry shrinks from its democratic commitment and instead defers to the state to silence hate-mongers. By disengaging from public debate, citizens not only become less sovereign, they also run the risk of losing the battle against the hate-monger. It is also useful for society to know who is spreading hate. By identifying and monitoring their messages, we are able to act quickly if hateful expression turns into hateful action. Furthermore, those expressing hate will know that society is keeping watch on them.