diff --git a/actions/tree.py b/actions/tree.py
index 6a87ac4..4303fe6 100644
--- a/actions/tree.py
+++ b/actions/tree.py
@@ -177,7 +177,7 @@ class ActionTree():
         # it would parse out the trigger "TCP:flags:SA" and the tree as
         # "-tamper{TCP:flags:corrupt}"
         match = re.match(r"\[(\S*)\]-(\S*)|", string)
-        if not match or not match[0]:
+        if not match or not match.group(0):
             logger.error("Could not identify trigger or tree")
             return False