9. The computer-implemented method of claim 5 , further comprising: receiving a second request to access additional resources in the resource hierarchy; and evaluating at least one of the first representation or a third representation of the security policy to determine whether to grant access to the additional resources.
5. A computer-implemented method, comprising: receiving a request to access one or more resources of a resource hierarchy; determining a first representation of a security policy controlling access to the one or more resources, the first representation expressed using a first policy language; generating, in response to the request and based on the first representation, a second representation of the security policy in a second policy language, the second representation modifying a scope of authority granted by the first representation; retrieving one or more additional security policies for the request, the one or more additional security policies expressed in the second policy language; and evaluating the one or more additional security policies and the second representation to determine whether to grant access to the one or more resources.