diff --git a/placement/objects/resource_provider.py b/placement/objects/resource_provider.py
index 293c14a30..6a68209fc 100644
--- a/placement/objects/resource_provider.py
+++ b/placement/objects/resource_provider.py
@@ -1447,7 +1447,10 @@ class ResourceProviderList(base.ObjectListBase, base.VersionedObject):
             return []
         if rp_ids:
             query = query.where(rp.c.id.in_(rp_ids))
-        if forbidden_rp_ids:
+        # forbidden providers, if found, are mutually exclusive with matching
+        # providers above, so we only need to include this clause if we didn't
+        # use the positive filter above.
+        elif forbidden_rp_ids:
             query = query.where(~rp.c.id.in_(forbidden_rp_ids))
 
         if not resources: