diff --git a/check_source.py b/check_source.py
index c2907092..9b7f514b 100755
--- a/check_source.py
+++ b/check_source.py
@@ -82,7 +82,7 @@ class CheckSource(ReviewBot.ReviewBot):
         if kind == 'meta':
             self.review_messages['accepted'] = 'Skipping all checks for meta packages'
             return True
-        elif kind != 'source':
+        elif (kind is not None and kind != 'source'):
             self.review_messages['accepted'] = 'May not modify a non-source package of type {}'.format(kind)
             return False