diff --git a/app.py b/app.py
index f88570183..9060b38a4 100644
--- a/app.py
+++ b/app.py
@@ -87,7 +87,8 @@ if app.config['SECRET_KEY'] is None:
 
 # If the "preferred" scheme is https, then http is not allowed. Therefore, ensure we have a secure
 # session cookie.
-if app.config['PREFERRED_URL_SCHEME'] == 'https':
+if (app.config['PREFERRED_URL_SCHEME'] == 'https' and
+    not app.config.get('FORCE_NONSECURE_SESSION_COOKIE', False)):
   app.config['SESSION_COOKIE_SECURE'] = True
 
 # Load features from config.