In fact, this website outlines examples of Ahmed Deedat pushing things so far as to almost fall under prosecution and deportation for his outrageous statements against Christianity. However, the form of response most often documented are two. Oral & written rebuttal and prayer. True, the website I direct you to contemplates a freedom of speech checkmark, but the fact is such checkmarks (AFAIK) are not implemented in Australia and throughout most of the Western World.
I have a book by Mr. Deedat. I found it on my desk at the UAEU one day. I took it, and looked it over understanding what it was. I have no idea where it is now a days. It could be at my parents home, it could be with me, it could be in bookshelf somewhere, it could be at a used bookstore, it could be in a box in a dank basement.
Funny, Islamic polemicists can slur Christians and our Bible all they want, but when a little harmless cartoon is drawn of their prophet how they squeal. Like little children running to hide behind their mommy's skirt.
Freedom of speech is about offensive speech. Everyone supports "she's a nice day out hey and so?" Does that help a drunk who needs to be told they are a drunk and needs help? Does that help a student understand they are a failure and will continue to be one until they start to study? Does that correct a boss who is about to take the company to ruin? Does that help a government about to take a nation on a wrong course? (Hehehe, lefty don't go there, keep it on topic and that is something we should agree on).