diff --git a/lib/plugins/db/RolePersistence.class.php b/lib/plugins/db/RolePersistence.class.php
index a66b9a0be2393894a4d719874263bc84189a686a..a0d01d5a4f0ef2faec75b6fe6b8891b5b5ffe8ec 100644
--- a/lib/plugins/db/RolePersistence.class.php
+++ b/lib/plugins/db/RolePersistence.class.php
@@ -198,6 +198,10 @@ class RolePersistence
      */
     public static function isAssignedRole($userid, $assignedrole, $institut_id = '')
     {
+        if (!$userid) {
+            return false;
+        }
+
         $faculty_id = $institut_id
                     ? Institute::find($institut_id)->fakultaets_id
                     : null;