[Mokka]

In my city, and I should also say country since the case went all the way to the supreme court,there was a rather famous case of a man standing on street corners and harassing people at our University with his hate speeches towards homosexuals.
He was tried by our various court systems as he appealed the ruling against him based on freedom of speech laws, but in the end he lost.

http://news.nationalpost.com/2013/02...-gay-crusader/

Now, what he did was not "mocking" gay people, but it does address the op's question of freedom of speech. Freedom of speech allowed should not be upheld if it insights hatred to a group of individuals based on their race, religion, sexual preferences etc.