diff --git a/wcs/forms/backoffice.py b/wcs/forms/backoffice.py
index 84c2acdf4..0dc62677a 100644
--- a/wcs/forms/backoffice.py
+++ b/wcs/forms/backoffice.py
@@ -249,7 +249,8 @@ class FormDefUI(object):
                 r += htmltext('<td class="select"><input type="checkbox" name="select[]" ')
                 r += htmltext('value="%s"') % filled.id
                 workflow_roles = {}
-                workflow_roles.update(self.formdef.workflow_roles)
+                if self.formdef.workflow_roles:
+                    workflow_roles.update(self.formdef.workflow_roles)
                 if filled.workflow_roles:
                     workflow_roles.update(filled.workflow_roles)
                 for function_key, function_value in workflow_roles.items():