diff --git a/crow/include/crow/http_response.h b/crow/include/crow/http_response.h
index d3fdd03..6c28237 100644
--- a/crow/include/crow/http_response.h
+++ b/crow/include/crow/http_response.h
@@ -92,13 +92,18 @@
   }
 
   void end() {
-    if (!completed_) {
-      completed_ = true;
-
-      if (complete_request_handler_) {
-        complete_request_handler_();
-      }
+    if (completed_) {
+      CROW_LOG_ERROR << "Response was ended twice";
+      return;
     }
+    completed_ = true;
+    CROW_LOG_DEBUG << "calling completion handler";
+    if (!complete_request_handler_) {
+      CROW_LOG_ERROR << "completion handler was invalid";
+      return;
+    }
+    complete_request_handler_();
+
   }
 
   void end(boost::string_view body_part) {