What is a refugee, and why does it matter?

Earlier today, I was shown an article containing some disturbing allegations.  With my extremely cynical distrust of any journalist or politician, I tried to find out how accurate (or misleading) were the allegations that disturbed me.  I did not find a good answer, and so I sent the following inquiry to the Department of State.  (Links added afterward, as the submission form does not support HTML):

Does the Department of State and other branches of the federal government use the same definition of “refugee” as the UNHCR¹ in http://www.unhcr.org/pages/49c3646c125.html?

There were allegations made in January that the government was defining it as “threatened by their own government” and was accepting Muslim refugees in danger from Assad, but refusing Christians threatened by DAESH on the grounds that DAESH is not their legitimate government.  Is there any truth to these allegations?

What is the current policy?  President Obama has stated publicly that religion should not be a factor in evaluating refugees.  Are we applying other criteria that have the effect of altering the proportions of Christians, Jews, Muslims, Yazidis, Zoroastrians, etc. who are accepted?

Others allege that our government is calling the slaughter of Yazidis “genocide” but not the slaughter of Christians.  Is this true? If so, how are they different?

If the current policy and the January policy are different, when did the change occur?

Can you cite for me CFR² or other _official_ documents answering these questions?

¹United Nations High Commissioner for Refugees
²Code of Federal Regulations

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