diff --git a/common/helpers.py b/common/helpers.py
index 3adc75d4..bd7ac32b 100644
--- a/common/helpers.py
+++ b/common/helpers.py
@@ -109,6 +109,8 @@ def is_valid_json(string):
         json_object = json.loads(string)
     except ValueError:
         return False
+    except TypeError:
+        return False
     return True