diff --git a/syncapi/types/types.go b/syncapi/types/types.go
index e0c3ee4f8..3cbf0f4e7 100644
--- a/syncapi/types/types.go
+++ b/syncapi/types/types.go
@@ -254,13 +254,15 @@ type InviteResponse struct {
 // NewInviteResponse creates an empty response with initialised arrays.
 func NewInviteResponse(ev gomatrixserverlib.HeaderedEvent) *InviteResponse {
 	res := InviteResponse{}
-	res.InviteState.Events = json.RawMessage{'[', ']'}
 	var unsigned struct {
 		InviteRoomState json.RawMessage `json:"invite_room_state"`
 	}
 	if err := json.Unmarshal(ev.Unsigned(), &unsigned); err == nil {
 		res.InviteState.Events = unsigned.InviteRoomState
 	}
+	if res.InviteState.Events == nil {
+		res.InviteState.Events = json.RawMessage{'[', ']'}
+	}
 	return &res
 }