diff --git a/http/http_connection.hpp b/http/http_connection.hpp
index d5d02e5..47f9432 100644
--- a/http/http_connection.hpp
+++ b/http/http_connection.hpp
@@ -342,7 +342,7 @@
 
         res.setHashAndHandleNotModified();
 
-        if (res.body().empty() && !res.jsonValue.empty())
+        if (res.body().empty() && !res.jsonValue.is_null())
         {
             using http_helpers::ContentType;
             std::array<ContentType, 3> allowed{