diff --git a/src/security/sec-policy-self-verify.hpp b/src/security/sec-policy-self-verify.hpp
index 1b17646..1e95d59 100644
--- a/src/security/sec-policy-self-verify.hpp
+++ b/src/security/sec-policy-self-verify.hpp
@@ -48,7 +48,7 @@
    */
   virtual ptr_lib::shared_ptr<ValidationRequest>
   checkVerificationPolicy
-    (const ptr_lib::shared_ptr<Data>& data, int stepCount, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed);
+    (const ptr_lib::shared_ptr<const Data>& data, int stepCount, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed);
 
   /**
    * Check whether the received interest packet complies with the verification policy, and get the indication of the next verification step.
@@ -62,7 +62,7 @@
    */
   virtual ptr_lib::shared_ptr<ValidationRequest>
   checkVerificationPolicy
-    (const ptr_lib::shared_ptr<Interest>& interest, int stepCount, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed);
+    (const ptr_lib::shared_ptr<const Interest>& interest, int stepCount, const OnVerified& onVerified, const OnVerifyFailed& onVerifyFailed);
 };
 
 }