diff --git a/nova/api/openstack/placement/handlers/allocation.py b/nova/api/openstack/placement/handlers/allocation.py
index 545957c29e29..b8b8e7aead26 100644
--- a/nova/api/openstack/placement/handlers/allocation.py
+++ b/nova/api/openstack/placement/handlers/allocation.py
@@ -20,6 +20,7 @@ from oslo_utils import encodeutils
 import webob
 
 from nova.api.openstack.placement import util
+from nova.api.openstack.placement import wsgi_wrapper
 from nova import exception
 from nova.i18n import _, _LE
 from nova import objects
@@ -157,7 +158,7 @@ def _serialize_allocations_for_resource_provider(allocations,
                              resource_provider=resource_provider)
 
 
-@webob.dec.wsgify
+@wsgi_wrapper.PlacementWsgify
 @util.check_accept('application/json')
 def list_for_consumer(req):
     """List allocations associated with a consumer."""
@@ -179,7 +180,7 @@ def list_for_consumer(req):
     return req.response
 
 
-@webob.dec.wsgify
+@wsgi_wrapper.PlacementWsgify
 @util.check_accept('application/json')
 def list_for_resource_provider(req):
     """List allocations associated with a resource provider."""
@@ -199,8 +200,7 @@ def list_for_resource_provider(req):
     except exception.NotFound as exc:
         raise webob.exc.HTTPNotFound(
             _("Resource provider '%(rp_uuid)s' not found: %(error)s") %
-            {'rp_uuid': uuid, 'error': exc},
-            json_formatter=util.json_error_formatter)
+            {'rp_uuid': uuid, 'error': exc})
 
     allocations = objects.AllocationList.get_all_by_resource_provider_uuid(
         context, uuid)
@@ -215,7 +215,7 @@ def list_for_resource_provider(req):
     return req.response
 
 
-@webob.dec.wsgify
+@wsgi_wrapper.PlacementWsgify
 @util.require_content('application/json')
 def set_allocations(req):
     context = req.environ['placement.context']
@@ -236,8 +236,7 @@ def set_allocations(req):
             raise webob.exc.HTTPBadRequest(
                 _("Allocation for resource provider '%(rp_uuid)s' "
                   "that does not exist.") %
-                {'rp_uuid': resource_provider_uuid},
-                json_formatter=util.json_error_formatter)
+                {'rp_uuid': resource_provider_uuid})
 
         resources = allocation['resources']
         for resource_class in resources:
@@ -264,21 +263,19 @@ def set_allocations(req):
     except exception.InvalidInventory as exc:
         LOG.exception(_LE("Bad inventory"))
         raise webob.exc.HTTPConflict(
-            _('Unable to allocate inventory: %(error)s') % {'error': exc},
-            json_formatter=util.json_error_formatter)
+            _('Unable to allocate inventory: %(error)s') % {'error': exc})
     except exception.ConcurrentUpdateDetected as exc:
         LOG.exception(_LE("Concurrent Update"))
         raise webob.exc.HTTPConflict(
             _('Inventory changed while attempting to allocate: %(error)s') %
-            {'error': exc},
-            json_formatter=util.json_error_formatter)
+            {'error': exc})
 
     req.response.status = 204
     req.response.content_type = None
     return req.response
 
 
-@webob.dec.wsgify
+@wsgi_wrapper.PlacementWsgify
 def delete_allocations(req):
     context = req.environ['placement.context']
     consumer_uuid = util.wsgi_path_item(req.environ, 'consumer_uuid')
@@ -295,13 +292,11 @@ def delete_allocations(req):
             raise webob.exc.HTPPNotFound(
                   _("Allocation for consumer with id %(id)s not found."
                     "error: %(error)s") %
-                  {'id': consumer_uuid, 'error': exc},
-                  json_formatter=util.json_error_formatter)
+                  {'id': consumer_uuid, 'error': exc})
     else:
         raise webob.exc.HTTPNotFound(
             _("No allocations for consumer '%(consumer_uuid)s'") %
-            {'consumer_uuid': consumer_uuid},
-            json_formatter=util.json_error_formatter)
+            {'consumer_uuid': consumer_uuid})
     LOG.debug("Successfully deleted allocations %s", allocations)
 
     req.response.status = 204
diff --git a/nova/api/openstack/placement/wsgi_wrapper.py b/nova/api/openstack/placement/wsgi_wrapper.py
new file mode 100644
index 000000000000..4aa8b789ba5f
--- /dev/null
+++ b/nova/api/openstack/placement/wsgi_wrapper.py
@@ -0,0 +1,33 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+"""Extend functionality from webob.dec.wsgify for Placement API."""
+
+import webob
+
+from oslo_log import log as logging
+from webob.dec import wsgify
+
+from nova.api.openstack.placement import util
+
+LOG = logging.getLogger(__name__)
+
+
+class PlacementWsgify(wsgify):
+
+    def call_func(self, req, *args, **kwargs):
+        """Add json_error_formatter to any webob HTTPExceptions."""
+        try:
+            super(PlacementWsgify, self).call_func(req, *args, **kwargs)
+        except webob.exc.HTTPException as exc:
+            LOG.debug("Placement API returning an error response: %s", exc)
+            exc.json_formatter = util.json_error_formatter
+            raise
diff --git a/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml b/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml
index 86b6e7072118..61c060805774 100644
--- a/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml
+++ b/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml
@@ -17,6 +17,8 @@ tests:
 - name: get allocations no consumer is 404
   GET: /allocations
   status: 404
+  response_json_paths:
+     $.errors[0].title: Not Found
 
 - name: get allocations is empty dict
   GET: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
@@ -32,6 +34,8 @@ tests:
           - resources:
               DISK_GB: 10
   status: 400
+  response_json_paths:
+     $.errors[0].title: Bad Request
 
 - name: create the resource provider
   POST: /resource_providers
@@ -47,6 +51,8 @@ tests:
   request_headers:
       content-type: application/json
   status: 400
+  response_json_paths:
+      $.errors[0].title: Bad Request
 
 - name: put an allocation violate schema
   PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
@@ -59,6 +65,8 @@ tests:
             resources:
                 cow: 10
   status: 400
+  response_json_paths:
+     $.errors[0].title: Bad Request
 
 - name: put an allocation no inventory
   PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
@@ -71,6 +79,8 @@ tests:
             resources:
                 DISK_GB: 10
   status: 409
+  response_json_paths:
+     $.errors[0].title: Conflict
 
 - name: post some inventory
   POST: /resource_providers/$ENVIRON['RP_UUID']/inventories
@@ -145,6 +155,8 @@ tests:
   status: 400
   response_strings:
       - No such resource class COWS
+  response_json_paths:
+      $.errors[0].title: Bad Request
 
 - name: delete allocation
   DELETE: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
@@ -155,10 +167,14 @@ tests:
   status: 404
   response_strings:
       - No allocations for consumer '599ffd2d-526a-4b2e-8683-f13ad25f9958'
+  response_json_paths:
+      $.errors[0].title: Not Found
 
 - name: delete allocation of unknown consumer id
   DELETE: /allocations/da78521f-bf7e-4e6e-9901-3f79bd94d55d
   status: 404
+  response_json_paths:
+      $.errors[0].title: Not Found
 
 - name: redo an allocation
   PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
@@ -217,6 +233,8 @@ tests:
 - name: confirm 404 for allocations of bad resource provider
   GET: /resource_providers/cb8a3007-b93a-471f-9e1f-4d58355678bd/allocations
   status: 404
+  response_json_paths:
+      $.errors[0].title: Not Found
 
 - name: check allocations by consumer id
   GET: /allocations/833f0885-f78c-4788-bb2b-3607b0656be7
@@ -358,3 +376,5 @@ tests:
   status: 400
   response_strings:
       - Allocation for resource provider 'be8b9cba-e7db-4a12-a386-99b4242167fe' that does not exist
+  response_json_paths:
+      $.errors[0].title: Bad Request