diff --git a/data/model/tag.py b/data/model/tag.py
index f533e9a08..afc0b36cb 100644
--- a/data/model/tag.py
+++ b/data/model/tag.py
@@ -148,10 +148,12 @@ def garbage_collect_tags(repo):
                                  .join(RepositoryTag)
                                  .where(RepositoryTag.id << tags_to_delete))
 
-      num_deleted_manifests = (TagManifest
-                               .delete()
-                               .where(TagManifest.id << manifests_to_delete)
-                               .execute())
+      num_deleted_manifests = 0
+      if len(manifests_to_delete) > 0:
+        num_deleted_manifests = (TagManifest
+                                 .delete()
+                                 .where(TagManifest.id << manifests_to_delete)
+                                 .execute())
 
       num_deleted_tags = (RepositoryTag
                           .delete()