diff --git a/changelog.d/4263.bugfix b/changelog.d/4263.bugfix
new file mode 100644
index 0000000000000000000000000000000000000000..3dc1d7c7326a5dd9306b7ca2ffdedf5c04bcf465
--- /dev/null
+++ b/changelog.d/4263.bugfix
@@ -0,0 +1 @@
+Prevent crash on pagination.
diff --git a/synapse/handlers/pagination.py b/synapse/handlers/pagination.py
index 9d257ecf3151539579a121dadc029df136e8ab10..084c1503dae5af6db9d943ce9cb21ffd711c63d3 100644
--- a/synapse/handlers/pagination.py
+++ b/synapse/handlers/pagination.py
@@ -254,7 +254,7 @@ class PaginationHandler(object):
             })
 
         state = None
-        if event_filter and event_filter.lazy_load_members():
+        if event_filter and event_filter.lazy_load_members() and len(events) > 0:
             # TODO: remove redundant members
 
             # FIXME: we also care about invite targets etc.