diff --git a/stream_alert/rule_processor/classifier.py b/stream_alert/rule_processor/classifier.py
index de5895141..c5f5a6584 100644
--- a/stream_alert/rule_processor/classifier.py
+++ b/stream_alert/rule_processor/classifier.py
@@ -347,5 +347,6 @@ def _convert_type(cls, payload, schema):
 
             else:
                 LOGGER.error('Unsupported schema type: %s', value)
+                return False
 
         return True