diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index b36eec0993160dbf25ead459125cc8f5b1c2da6b..48548f8c4082e3bcc47c3bdf517f1d065c66bd78 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -66,7 +66,6 @@ def prune_event(event):
             "users_default",
             "events",
             "events_default",
-            "events_default",
             "state_default",
             "ban",
             "kick",