@@ -277,9 +277,13 @@ def deserialize(self, content):
             content = content.decode("utf-8")
         except AttributeError:
             pass
-        body = json.loads(content)
-        if self._data_wrapper and isinstance(body, dict) and "data" in body:
-            body = body["data"]
+        try:
+            body = json.loads(content)
+        except json.decoder.JSONDecodeError:
+            body = content
+        else:
+            if self._data_wrapper and "data" in body:
+                body = body["data"]
         return body
 
     @property
 
@@ -22,6 +22,7 @@
 
 __author__ = "jcgregorio@google.com (Joe Gregorio)"
 
+import io
 import httplib2
 import json
 import pkg_resources
@@ -31,11 +32,11 @@
 
 import googleapiclient.model
 
-
 from googleapiclient.errors import HttpError
 from googleapiclient.model import JsonModel
 
 _LIBRARY_VERSION = pkg_resources.get_distribution("google-api-python-client").version
+CSV_TEXT_MOCK = 'column1,column2,column3\nstring1,1.2,string2'
 
 
 class Model(unittest.TestCase):
@@ -290,6 +291,24 @@ def test_no_data_wrapper_deserialize(self):
         content = model.response(resp, content)
         self.assertEqual(content, {"data": "is good"})
 
+    def test_no_data_wrapper_deserialize_text_format(self):
+        model = JsonModel(data_wrapper=False)
+        resp = httplib2.Response({"status": "200"})
+        resp.reason = "OK"
+        content = CSV_TEXT_MOCK
+        content = model.response(resp, content)
+        self.assertEqual(content, CSV_TEXT_MOCK)
+
+    def test_no_data_wrapper_deserialize_raise_type_error(self):
+        buffer = io.StringIO()
+        buffer.write('String buffer')
+        model = JsonModel(data_wrapper=False)
+        resp = httplib2.Response({"status": "500"})
+        resp.reason = "The JSON object must be str, bytes or bytearray, not StringIO"
+        content = buffer
+        with self.assertRaises(TypeError):
+            model.response(resp, content)
+
     def test_data_wrapper_deserialize(self):
         model = JsonModel(data_wrapper=True)
         resp = httplib2.Response({"status": "200"})