How do you know if a comment is hate speech?
The Supreme Court of Canada says a comment is NOT hate speech if it "merely" ridicules you or subjects you to embarrassment.
It IS hate speech if it incites hatred against you.
In other words, if you draw a line between an innocuous remark ("I don't like your hair") through objectionable ("God says that gay people are evil and should be shunned) to vicious ("Let's kill all the queers/Indians/etc"; or "Science says disabled people should be euthanized" it is clear that innocuous remarks are not hate speech. It is clear that remarks inciting violence against an identified group ARE hate speech. Whether the remark about God's opinion about gays (a) is hate speech or (b) is protected by freedom of religion/conscience/expression depends on the view of the judge hearing the case.
When the judge hears the case, she is supposed to consider the question not from the perspective of the group being maligned but from an objective point of view; and she is supposed to ask herself whether an 'objective' person hearing the remark and knowing the relevant circumstances would understand it to be hate speech.
The general idea - which is one we all support - is that truly hateful speech should be banned; but free speech is precious and should be limited only for very good reasons. However we might disagree vehemently about whether a particular remark is or isn't 'hate speech'.