diff --git a/src/RegToken.c b/src/RegToken.c
index fa041d3..2b318f6 100644
--- a/src/RegToken.c
+++ b/src/RegToken.c
@@ -238,6 +238,7 @@ RegTokenCreate(Db * db, char *name, char *owner, UInt64 expires, Int64 uses, int
     ret->uses = uses;
     ret->created_on = timestamp;
     ret->expires_on = expires;
+    /* TODO: #37 type mismatch: UserEncodePrivileges() returns a JsonValue */
     ret->grants = UserEncodePrivileges(privileges);
 
     return ret;
diff --git a/src/Routes/RoutePrivileges.c b/src/Routes/RoutePrivileges.c
index 4ffa480..44ca311 100644
--- a/src/Routes/RoutePrivileges.c
+++ b/src/Routes/RoutePrivileges.c
@@ -98,15 +98,15 @@ ROUTE_IMPL(RoutePrivileges, path, argp)
             switch (HttpRequestMethodGet(args->context))
             {
                 case HTTP_POST:
-                    privileges = UserDecodePrivileges(JsonValueAsArray(val));
+                    privileges = UserDecodePrivileges(val);
                     break;
                 case HTTP_PUT:
                     privileges = UserGetPrivileges(user);
-                    privileges |= UserDecodePrivileges(JsonValueAsArray(val));
+                    privileges |= UserDecodePrivileges(val);
                     break;
                 case HTTP_DELETE:
                     privileges = UserGetPrivileges(user);
-                    privileges &= ~UserDecodePrivileges(JsonValueAsArray(val));
+                    privileges &= ~UserDecodePrivileges(val);
                     break;
                 default:
                     /* Impossible */
@@ -124,7 +124,7 @@ ROUTE_IMPL(RoutePrivileges, path, argp)
             /* Fall through */
         case HTTP_GET:
             response = HashMapCreate();
-            HashMapSet(response, "privileges", JsonValueArray(UserEncodePrivileges(UserGetPrivileges(user))));
+            HashMapSet(response, "privileges", UserEncodePrivileges(UserGetPrivileges(user)));
             break;
         default:
             HttpResponseStatus(args->context, HTTP_BAD_REQUEST);
diff --git a/src/Routes/RouteRegister.c b/src/Routes/RouteRegister.c
index 3527219..7f51744 100644
--- a/src/Routes/RouteRegister.c
+++ b/src/Routes/RouteRegister.c
@@ -276,6 +276,7 @@ ROUTE_IMPL(RouteRegister, path, argp)
 
                 if (info)
                 {
+                    /* TODO: #37 type mismatch: info->grants is a string array. */
                     UserSetPrivileges(user, UserDecodePrivileges(info->grants));
                     RegTokenClose(info);
                     RegTokenFree(info);
diff --git a/src/User.c b/src/User.c
index d13ab90..1996255 100644
--- a/src/User.c
+++ b/src/User.c
@@ -749,7 +749,7 @@ UserGetPrivileges(User * user)
         return USER_NONE;
     }
 
-    return UserDecodePrivileges(JsonValueAsArray(HashMapGet(DbJson(user->ref), "privileges")));
+    return UserDecodePrivileges(HashMapGet(DbJson(user->ref), "privileges"));
 }
 
 int
@@ -768,7 +768,7 @@ UserSetPrivileges(User * user, int privileges)
         return 1;
     }
 
-    val = JsonValueArray(UserEncodePrivileges(privileges));
+    val = UserEncodePrivileges(privileges);
     if (!val)
     {
         return 0;
@@ -779,17 +779,19 @@ UserSetPrivileges(User * user, int privileges)
 }
 
 int
-UserDecodePrivileges(Array * arr)
+UserDecodePrivileges(JsonValue * val)
 {
     int privileges = USER_NONE;
-
+    Array *arr;
     size_t i;
 
-    if (!arr)
+    if (!val || JsonValueType(val) != JSON_ARRAY)
     {
         goto finish;
     }
 
+    arr = JsonValueAsArray(val);
+
     for (i = 0; i < ArraySize(arr); i++)
     {
         JsonValue *val = ArrayGet(arr, i);
@@ -846,7 +848,7 @@ UserDecodePrivilege(const char *p)
     }
 }
 
-Array *
+JsonValue *
 UserEncodePrivileges(int privileges)
 {
     Array *arr = ArrayCreate();
@@ -878,7 +880,7 @@ UserEncodePrivileges(int privileges)
 #undef A
 
 finish:
-    return arr;
+    return JsonValueArray(arr);
 }
 
 UserId *
diff --git a/src/include/User.h b/src/include/User.h
index bd30803..ec266ec 100644
--- a/src/include/User.h
+++ b/src/include/User.h
@@ -286,13 +286,13 @@ extern int UserSetPrivileges(User *, int);
  * Decode the JSON that represents the user privileges into a packed
  * bit field for simple manipulation.
  */
-extern int UserDecodePrivileges(Array *);
+extern int UserDecodePrivileges(JsonValue *);
 
 /**
  * Encode the packed bit field that represents user privileges as a
  * JSON value.
  */
-extern Array *UserEncodePrivileges(int);
+extern JsonValue *UserEncodePrivileges(int);
 
 /**
  * Convert a string privilege into its bit in the bit field. This is