diff --git a/keystone/middleware/core.py b/keystone/middleware/core.py
index 0f6c1e6333..aa02c62b24 100644
--- a/keystone/middleware/core.py
+++ b/keystone/middleware/core.py
@@ -98,21 +98,25 @@ class JsonBodyMiddleware(wsgi.Middleware):
 
     """
     def process_request(self, request):
-        # Ignore unrecognized content types. Empty string indicates
-        # the client did not explicitly set the header
-        if not request.content_type in ('application/json', ''):
-            return
-
+        # Abort early if we don't have any work to do
         params_json = request.body
         if not params_json:
             return
 
+        # Reject unrecognized content types. Empty string indicates
+        # the client did not explicitly set the header
+        if not request.content_type in ('application/json', ''):
+            e = exception.ValidationError(attribute='application/json',
+                                          target='Content-Type header')
+            return wsgi.render_exception(e)
+
         params_parsed = {}
         try:
             params_parsed = json.loads(params_json)
         except ValueError:
-            msg = 'Malformed json in request body'
-            raise webob.exc.HTTPBadRequest(explanation=msg)
+            e = exception.ValidationError(attribute='valid JSON',
+                                          target='request body')
+            return wsgi.render_exception(e)
         finally:
             if not params_parsed:
                 params_parsed = {}
diff --git a/tests/test_middleware.py b/tests/test_middleware.py
index a5740acd56..fca3977565 100644
--- a/tests/test_middleware.py
+++ b/tests/test_middleware.py
@@ -90,9 +90,8 @@ class JsonBodyMiddlewareTest(test.TestCase):
         req = make_request(body='{"arg1": "on',
                            content_type='application/json',
                            method='POST')
-        _middleware = middleware.JsonBodyMiddleware(None)
-        self.assertRaises(webob.exc.HTTPBadRequest,
-                          _middleware.process_request, req)
+        resp = middleware.JsonBodyMiddleware(None).process_request(req)
+        self.assertEqual(resp.status_int, 400)
 
     def test_no_content_type(self):
         req = make_request(body='{"arg1": "one", "arg2": ["a"]}',
@@ -105,6 +104,12 @@ class JsonBodyMiddlewareTest(test.TestCase):
         req = make_request(body='{"arg1": "one", "arg2": ["a"]}',
                            content_type='text/plain',
                            method='POST')
+        resp = middleware.JsonBodyMiddleware(None).process_request(req)
+        self.assertEqual(resp.status_int, 400)
+
+    def test_unrecognized_content_type_without_body(self):
+        req = make_request(content_type='text/plain',
+                           method='GET')
         middleware.JsonBodyMiddleware(None).process_request(req)
         params = req.environ.get(middleware.PARAMS_ENV, {})
         self.assertEqual(params, {})