diff --git a/api_core/tests/unit/test_iam.py b/api_core/tests/unit/test_iam.py
index 788392e48cada..c85a458356b6d 100644
--- a/api_core/tests/unit/test_iam.py
+++ b/api_core/tests/unit/test_iam.py
@@ -117,6 +117,10 @@ def test___delitem___hit(self):
 
     def test___delitem___miss(self):
         policy = self._make_one()
+        policy.bindings = [
+            {"role": "a", "members": set(["phred@example.com"])},
+            {"role": "b", "members": set(["phred@example.com"])}
+        ]
         with pytest.raises(KeyError):
             del policy["nonesuch"]