Otherwise, all that gesticulating about the ‘international rules based order’ and all that outrage at Russian war crimes is just empty posturing. And justifying war crimes because the enemy has committed them renders the Geneva convention meaningless.

Yet it is meaningless in the context of nuclear countries. International law works more as a suggestion as you can't forcibly enforce it against country that just says no to you.

But yes if confirmed by 3rd parties that Ukraine is responsible for the death of the journalist in the manner Russian Foreign Ministry described there should be consequences.