1 files changed, 2 insertions, 1 deletions
diff --git a/synapse/storage/databases/state/store.py b/synapse/storage/databases/state/store.py
index 875dba3349..f7a59c8992 100644
--- a/synapse/storage/databases/state/store.py
+++ b/synapse/storage/databases/state/store.py
@@ -284,7 +284,8 @@ class StateGroupDataStore(StateBackgroundUpdateStore, SQLBaseStore):
         Returns:
             Dict of state group to state map.
         """
-        state_filter = state_filter or StateFilter.all()
+        if state_filter is None:
+            state_filter = StateFilter.all()
 
         member_filter, non_member_filter = state_filter.get_member_split()