"So farewell then Anjem Choudary. At least for a few years. Britain’s biggest loudmouth Islamist has finally been convicted in the UK for encouraging support for Isis. He now faces up to ten years in prison."
http://blogs.spectator.co.uk/2016/08/bad-day-anjem-choudary-good-day-secular-law/
He used free speech protections to promote terrorism.
http://www.nbcnews.com/news/world/how-anjem-choudary-used-free-speech-recruit-isis-n633376
Good example of how there are reasonable restrictions on free speech. Free speech which incites violence may reasonably be curtailed.