Access control is one of the most fundamental and widely used security mechanisms. Access control mechanisms con- trol which principals such as users or processes have ac- cess to which resources in a system. To facilitate manag- ing and maintaining access control, access control policies are increasingly written in specification languages such as XACML. The specification of access control policies itself is often a challenging problem. Furthermore, XACML is in- tentionally designed to be generic: it provides the freedom in describing access control policies, which are well-known or invented ones. But the flexibility and expressiveness pro- vided by XACML come at the cost of complexity, verbosity, and lack of desirable-property enforcement. Often common properties for specific access control policies may not be satisfied when these policies are specified in XACML, caus- ing the discrepancy between what the policy authors intend to specify and what the actually specified XACML policies reflect. In this position paper, we propose an approach for conducting conformance checking of access control policies specified in XACML based on existing verification and test- ing tools for XACML policies.