Steve - this new legislation is a natural outgrowth of previous UK legislation protecting specifically Jews and Sikhs. Of course the Moslems now want to be added to "protected classes" - nothing surprising in that! Either all citizens are protected or none are. Naming classes of "designated victims" is pointless at best; claiming the original 2 were "racial", not "religious" categories is laughable, in the case of jews at any rate.
Since you asked about related US legislation: "Terminiello v. City of Chicago" is the most directly relevant Supreme Court decision:
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''A function of free speech under our system of government,'' wrote Justice Douglas for the majority, ''is to invite dispute. It may indeed best serve its high purpose when it induces a condition of unrest, creates dissatisfaction with conditions as they are, or even stirs people to anger.
Speech is often provocative and challenging. It may strike at prejudices and preconceptions and have profound unsettling effects as it presses for acceptance of an idea. That is why freedom of speech, though not absolute, . . . is nevertheless protected against censorship or punishment, unless shown likely to produce a clear and present danger of a serious substantive evil that rises far above public inconvenience, annoyance, or unrest.''
http://supreme.lp.findlaw.com/constitution/amendment01/10.html#1
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