Why is he facing any charges?
The man who converted to Christianity? Because he got caught in Afghanistan with a Bible.
Because Muhammad said: "He who relinquishes his faith, kill him". This was recorded in Sahi of al-Bukhari (part 9, p.19). A number of Islamic scholars also ascribe this statement to Muhammad. Let me suggest that you read "Behind the Veil - Unmasking Islam" by Abd El Achafi. This, and other books on Islam, can be purchased from Voice of the Martyrs .
You asked -- "Why is he facing any charges?"
He's facing the charge of converting to another religion from Islam. That's a crime in Islam. That's a crime that has the death penalty.
This is not a joke. It's really a crime. If you leave Islam, you're in danger of either being murdered (and no Muslim would be held accountable for murdering an infidel) -- or -- being convicted and killed as a penalty of this crime.
And, everyone who is born into a Muslim family is *automatically* a Muslim (at the instant of birth). Since no one can leave without being murdered, you can see why Islam is "growing" very quickly.
Regards,
Star Traveler