diff --git a/moto/core/responses.py b/moto/core/responses.py
index 278a24dc..ca5b9f7d 100644
--- a/moto/core/responses.py
+++ b/moto/core/responses.py
@@ -574,7 +574,7 @@ class AWSServiceSpec(object):
 
     def __init__(self, path):
         self.path = resource_filename('botocore', path)
-        with open(self.path) as f:
+        with open(self.path, "rb") as f:
             spec = json.load(f)
         self.metadata = spec['metadata']
         self.operations = spec['operations']