I should have chosen my words more carefully, I didn't mean actual policy. Standard practice would have been better.

I'll take your word for it. I did wind up looking for examples of similar cases, but the only ones I could find from this century were two instances from Pakistan where immunity was not waived and it probably would have been a bad idea. We have demanded other countries waive immunity when we were on the opposite end of this though, and they've done it.