Most of Islamic law is about the treatment of non-believers, and non of it is good.
Moreover, one can consider that the issuance of legal documents by the OIC that would essentially lead to defining “terrorism” as the taking of a Muslem’s life without right, and NOTHING else! as why these groups can say they oppose “terrorism” and yet often support it.
If they are following the line set forth by those in authority within the Islamic legal community at large “terrorism” does not include any acts taken against no-Muslims.
Here’s a link to the first in a series of videos about Islamic Law (determining the sort of thret doctrine it’s tenants warrant) that uses, as their point of reference, things written by Muslims, for Muslims, and recognized as authoratative by same ... IOW what they say and write to each other: http://youtu.be/nhZe7eZK4dw