diff --git a/presubmit_canned_checks.py b/presubmit_canned_checks.py
index 20b939321..2cd3a81aa 100644
--- a/presubmit_canned_checks.py
+++ b/presubmit_canned_checks.py
@@ -627,20 +627,20 @@ def CheckBuildbotPendingBuilds(input_api, output_api, url, max_pendings,
 
 
 def CheckOwners(input_api, output_api, source_file_filter=None):
-  affected_files = set(input_api.change.AffectedFiles(source_file_filter))
+  affected_files = set([f.LocalPath() for f in
+      input_api.change.AffectedFiles(source_file_filter)])
   owners_db = input_api.owners_db
 
-  if input_api.is_commiting:
+  if input_api.is_committing:
     missing_files = owners_db.FilesNotCoveredBy(affected_files,
                                                 input_api.change.approvers)
     if missing_files:
       return [output_api.PresubmitPromptWarning('Missing approvals for: %s' %
               ','.join(missing_files))]
     return []
-  else:
-    if not input_api.change.get('R', None):
-      suggested_reviewers = owners_db.OwnersFor(affected_files)
+  elif input_api.change.tags.get('R'):
+    return []
 
-      # TODO(dpranke): consider getting multiple covering sets of reviewers
-      # and displaying them somehow?
-      input_api.change['R'] = ','.join(suggested_reviewers)
+  suggested_reviewers = owners_db.ReviewersFor(affected_files)
+  # TODO(dpranke): Actually propagate the info back.
+  return []