diff -u b/commerce_discount.rules.inc b/commerce_discount.rules.inc
--- b/commerce_discount.rules.inc
+++ b/commerce_discount.rules.inc
@@ -423,16 +423,6 @@
   return $items;
 }
 
-function _commerce_discount_remove_order_discount($discounts_array, $discount_name) {
-  $new_discounts_array = $discounts_array;
-
-  if (($key = array_search($discount_name, $new_discounts_array)) !== FALSE) {
-    unset($new_discounts_array[$key]);
-  }
-
-  return $new_discounts_array;
-}
-
 /**
  * Rules callback: executes the "Check discount compatibility" condition.
  *