diff --git a/model/PFASmarty.php b/model/PFASmarty.php
index 7c5d9cb5..d17f0946 100644
--- a/model/PFASmarty.php
+++ b/model/PFASmarty.php
@@ -138,7 +138,7 @@ class PFASmarty
      * */
     public function sanitise($data)
     {
-        if (is_object($data)) {
+        if (is_object($data) || is_null($data)) {
             return $data; // can't handle
         }