diff --git a/caveclient/chunkedgraph.py b/caveclient/chunkedgraph.py
index 71dc761b..053a1024 100644
--- a/caveclient/chunkedgraph.py
+++ b/caveclient/chunkedgraph.py
@@ -814,10 +814,12 @@ def get_latest_roots(self, root_id, timestamp=None, timestamp_future=None):
         if timestamp_future is not None:
             logger.warning("timestamp_future is deprecated, use timestamp instead")
             timestamp = timestamp_future
-
+        
         if timestamp is None:
             timestamp = datetime.datetime.now(datetime.timezone.utc)
-
+        elif timestamp.tzinfo is None:
+            timestamp = timestamp.replace(tzinfo=datetime.timezone.utc)
+            
         # or if timestamp_root is less than timestamp_future
         if (timestamp is None) or (timestamp_root < timestamp):
             lineage_graph = self.get_lineage_graph(