This thread has produced a considerable amount of heat and noise but not much light.
Is there a complete ban on any discussion regarding immigration, ethnic minorities and race generally? Personally, that strikes me as verging on totalitarianism and unacceptable. Alternatively, is this a complaint about the half-baked, barely literate racist diatribe spouted by some members when addressing any issue regarding gentlemen of the Commonwealth? In which case, "fair comment, you know who you are, cut it out." "Love thy Neighbour," starring Jack Smethurst, ended years ago, so get over it.
Perhaps a more tactful solution is to remind members that making racist comments is unacceptable in a civilized country.
Unless, of course, they're really funny comments, in which case...