diff --git a/password_policy.module b/password_policy.module
index a086de2..3d4f8b6 100644
--- a/password_policy.module
+++ b/password_policy.module
@@ -665,7 +665,7 @@ function _password_policy_constraint_validate($pass, &$account) {
   _password_policy_constraints();
 
   $error = NULL;
-  $roles = is_array($account->roles) ? array_keys($account->roles) : array();
+  $roles = (isset($account->roles) && is_array($account->roles)) ? array_keys($account->roles) : array();
   $policy = _password_policy_load_active_policy($roles);
   if (!empty($policy['policy'])) {
     foreach ($policy['policy'] as $key => $value) {