diff --git a/handler.go b/handler.go
index d71270514d80aa364f55df47c87549dea92a82f1..7c2581e1320784c053d9fd0c3610dae078303d26 100644
--- a/handler.go
+++ b/handler.go
@@ -272,7 +272,7 @@ func (h *handler) handleCallMsg(ctx *callProc, r *Request) *Response {
 		return r.errorResponse(&invalidRequestError{"invalid request"})
 	default:
 		res := r.errorResponse(&invalidRequestError{"invalid request"})
-		res.ID = nil
+		res.ID = NewNullIDPtr()
 		return res
 	}
 }
diff --git a/json_wire.go b/json_wire.go
index 0489515fa6b0b745b98f3740ebe3a85d81fb0c97..6df978cd9caee613b7ab3b8be976dadab98edf8c 100644
--- a/json_wire.go
+++ b/json_wire.go
@@ -48,6 +48,8 @@ type ID struct {
 	number int64
 
 	null bool
+
+	empty bool
 }
 
 // compile time check whether the ID implements a fmt.Formatter, json.Marshaler and json.Unmarshaler interfaces.
@@ -91,6 +93,9 @@ func (id *ID) Format(f fmt.State, r rune) {
 
 // get the raw message
 func (id *ID) RawMessage() json.RawMessage {
+	if id.empty {
+		return nil
+	}
 	if id == nil {
 		return null
 	}