Well, this is nothing like my area. However, the conflict between proper research, and what is considered "politically correct" is interesting, and I'm sure the whole political correctness thing can block good research. Perhaps the key is to approach non-French institutions. I suppose it depends on your hypothesis, and which minority groups you're looking at, but there must be bodies either in this country (could you compare representation between UK and French TV?) or in the EU. However, I can't really help you.
Anyone?